Castleport Test Prep

Free NLN NEX Practice Test

This free NLN NEX practice test contains 145 original questions with explanations: 50 Verbal, 40 Math, and 55 Science. It is unofficial and requires no signup.

Question 1 · Word Knowledge · Word Analysis

The patient's dizziness was transient; it faded within a minute after she sat down.

As used in the sentence, transient most nearly means

A. mild
B. recurring
C. alarming
D. brief

Answer: D. brief

The clue is “faded within a minute,” so the dizziness didn't last. Brief matches, and it matches the dictionary sense of transient: passing in and out of existence in a short time. Mild is about how strong something is, and the sentence never says. Recurring means happening again; nothing says the dizziness came back. Alarming describes a reaction the sentence doesn't give. On context-clue questions, find the phrase that explains the word, then pick the option that matches that phrase.

Source: Merriam-Webster, “transient” (adjective, sense 1a).

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Question 1 · Verbal · Word Knowledge

The patient's dizziness was transient; it faded within a minute after she sat down. As used in the sentence, transient most nearly means

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Percentages use presented-item denominators: 145 overall, 50 Verbal, 40 Math, and 55 Science. This is not an NLN percentile, composite, pass prediction, or admissions verdict.

Verbal practice questions

Word Knowledge (Questions 1–25)

In Questions 1–15, work out each word from context clues or word parts. Questions 16–25 test vocabulary directly.

Questions 1–50 cover 25 Word Knowledge and 25 Reading Comprehension items. Choose an answer before opening its explanation. For a scored attempt, record your first answer; an answer viewed before you respond counts as unanswered. Optional subject pacing and its limits appear below the practice questions.

Verbal · Math · Science · Score your practice test

Question 2 · Word Knowledge · Word Analysis

The lab assistant was meticulous, recording every measurement to a tenth of a gram and dating each page of her notebook.

As used in the sentence, meticulous most nearly means

A. hurried and sloppy
B. easily distracted
C. private and secretive
D. extremely careful

Answer: D. extremely careful

The details (every measurement to a tenth of a gram, every page dated) describe someone who pays close attention to small things. That is extremely careful, the core meaning of meticulous. Hurried and sloppy work skips details instead of adding them. Easily distracted is the opposite of what the sentence shows. Private and secretive is about hiding information, and nothing suggests she hid her notes.

Source: Merriam-Webster, “meticulous”.

Question 3 · Word Knowledge · Word Analysis

Unlike the crowded forest along the river, the hillside had only sparse vegetation: a few shrubs scattered among the rocks.

As used in the sentence, sparse most nearly means

A. thick and tangled
B. thinly scattered
C. brightly colored
D. recently planted

Answer: B. thinly scattered

Two clues point the same way. “Unlike the crowded forest” sets up a contrast, and “a few shrubs scattered among the rocks” describes the hillside directly. So sparse means thinly scattered. Thick and tangled describes the crowded forest, the thing being contrasted. Brightly colored and recently planted add ideas (color, timing) the sentence never mentions.

Source: Merriam-Webster, “sparse”.

Question 4 · Word Knowledge · Word Analysis

Maria was candid with her advisor, openly admitting that she had skipped several chemistry lectures.

As used in the sentence, candid most nearly means

A. angry and upset
B. frank and honest
C. vague and unclear
D. sorry and apologetic

Answer: B. frank and honest

“Openly admitting” is an example clue: Maria told the truth plainly. That is frank and honest. Vague and unclear is the opposite of open. Angry and upset isn't suggested anywhere. Sorry and apologetic is the tempting trap. Admitting something is not the same as apologizing for it, and the sentence doesn't say she said sorry. Candid is about honesty, not regret.

Source: Merriam-Webster, “candid”.

Question 5 · Word Knowledge · Word Analysis

Because the roof was never repaired, the old barn continued to deteriorate; each winter, more boards rotted and fell away.

As used in the sentence, deteriorate most nearly means

A. attract visitors
B. stay the same
C. grow worse
D. be rebuilt

Answer: C. grow worse

Cause and effect gives it away: no repairs, and every winter more boards rot and fall. The barn's condition was getting worse, so deteriorate means grow worse. Stay the same contradicts “more boards rotted.” Be rebuilt is the opposite of what happened. Attract visitors has nothing to do with the clues.

Source: Merriam-Webster, “deteriorate”.

Question 6 · Word Knowledge · Word Analysis

Adding a second cashier helped alleviate the long lines, and customers were soon checking out quickly.

As used in the sentence, alleviate most nearly means

A. lengthen
B. ease
C. create
D. count

Answer: B. ease

The result, “customers were soon checking out quickly,” shows the lines got shorter. So alleviate means ease or lessen a problem. Lengthen and create would make the lines worse, which contradicts the outcome. Count doesn't change the lines at all.

Source: Merriam-Webster, “alleviate”.

Question 7 · Word Knowledge · Word Analysis

With a storm in the forecast, it seemed prudent to bring the lawn chairs inside before leaving for the weekend.

As used in the sentence, prudent most nearly means

A. sensible
B. expensive
C. unnecessary
D. exciting

Answer: A. sensible

The sentence gives a reason (a storm is coming) and a careful action taken ahead of time. Planning to avoid damage is sensible, which is what prudent means. Unnecessary contradicts the reason given. Expensive and exciting don't fit a quick chore done to protect the chairs.

Source: Merriam-Webster, “prudent”.

Question 8 · Word Knowledge · Word Analysis

The sign's directions were ambiguous: half the visitors turned left at the fountain, and the other half turned right.

As used in the sentence, ambiguous most nearly means

A. printed in small letters
B. recently updated
C. open to more than one meaning
D. strictly enforced

Answer: C. open to more than one meaning

The colon introduces the evidence: readers of the same sign went in opposite directions. The directions could be understood two ways, so ambiguous means open to more than one meaning. Printed in small letters might make a sign hard to read, but it wouldn't explain two different readings. Recently updated and strictly enforced aren't supported by anything in the sentence.

Source: Merriam-Webster, “ambiguous”.

Question 9 · Word Knowledge · Word Analysis

The word part bene- in beneficial means

A. against or opposite
B. before or earlier
C. many or several
D. good or well

Answer: D. good or well

Bene- comes from the Latin bene, “well,” which is why beneficial describes something that produces good results. Against is the meaning of anti- or contra-. Before is pre-. Many is multi- or poly-.

Source: Merriam-Webster, “benefit” (etymology: Latin bene, “well”).

Question 10 · Word Knowledge · Word Analysis

Based on its word parts, dehydrate most likely means

A. to add heat to
B. to measure the weight of
C. to protect from sunlight
D. to remove water from

Answer: D. to remove water from

Break the word apart. De- can mean “remove” or “take away,” and hydr means “water,” as in hydrant and hydrate. Together they give to remove water from. None of the other choices uses the water root, and none of them removes anything.

Source: Merriam-Webster, “dehydrate”.

Question 11 · Word Knowledge · Word Analysis

A bactericide is a substance that

A. feeds bacteria
B. kills bacteria
C. is produced by bacteria
D. detects bacteria

Answer: B. kills bacteria

The ending -cide means “killer,” as in insecticide or pesticide. So a bactericide kills bacteria. The other choices keep the bacteri- part but ignore what -cide adds.

Source: Merriam-Webster, “-cide” (combining form: killer).

Question 12 · Word Knowledge · Word Analysis

The prefix circum- in circumference means

A. across
B. half
C. inside
D. around

Answer: D. around

Circum- means “around,” and the circumference is the distance around a circle. Across describes a diameter, half is semi- or hemi-, and inside is intra-.

Source: Merriam-Webster, “circum-”.

Question 13 · Word Knowledge · Word Analysis

In the word atypical, the prefix a- means

A. between or among
B. again or back
C. not or without
D. above or over

Answer: C. not or without

Here a- means “not” or “without,” so atypical means not typical. Again is re-, above is super- or hyper-, and between is inter-.

Source: Merriam-Webster, “a-” (prefix: not, without).

Question 14 · Word Knowledge · Word Analysis

Based on its prefix, intercellular fluid is found

A. inside a single cell
B. only in the nucleus
C. on the surface of the skin
D. between cells

Answer: D. between cells

Inter- means “between” or “among,” as in interstate (between states). Intercellular fluid is fluid between cells. The trap is inside a single cell, which would be intracellular: intra- means “within.” The nucleus and skin surface aren't signaled by any part of the word.

Source: Merriam-Webster, “intercellular”.

Question 15 · Word Knowledge · Word Analysis

Using its word parts (in- + aud + -ible), inaudible means

A. easy to hear
B. not able to be heard
C. not able to be seen
D. able to be spoken

Answer: B. not able to be heard

In- means “not,” aud means “hear” (as in audio and audience), and -ible means “able to be.” Put together: not able to be heard. Easy to hear drops the in-. Not able to be seen swaps in a different sense; that would be invisible. Able to be spoken doesn't use the hearing root at all.

Source: Merriam-Webster, “inaudible”.

Question 16 · Word Knowledge · Vocabulary Development

The clinic had an adequate supply of gloves for the week.

Which word is closest in meaning to adequate?

A. excessive
B. expensive
C. sufficient
D. damaged

Answer: C. sufficient

Adequate means enough for the need, which is sufficient. Excessive means more than enough, a common mix-up. Expensive is about cost and damaged is about condition; neither describes quantity.

Source: Merriam-Webster, “adequate”.

Question 17 · Word Knowledge · Vocabulary Development

The instructor asked each student to give a concise answer.

Which word is closest in meaning to concise?

A. brief
B. detailed
C. creative
D. polite

Answer: A. brief

Concise means short and to the point, free of extra detail, so brief is the synonym. Detailed means including many particulars; it does not necessarily mean brief and to the point. Creative and polite describe other qualities an answer might have, not its length.

Source: Merriam-Webster, “concise”.

Question 18 · Word Knowledge · Vocabulary Development

He was reluctant to change his work schedule.

Which word is closest in meaning to reluctant?

A. hesitant
B. enthusiastic
C. qualified
D. careless

Answer: A. hesitant

Reluctant means unwilling or hesitating, so hesitant fits. Enthusiastic is the opposite. Qualified is about ability, not willingness: you can be qualified to do something and still be reluctant. Careless describes how something is done, not whether you want to do it.

Source: Merriam-Webster, “reluctant”.

Question 19 · Word Knowledge · Vocabulary Development

The crew wore protective suits to remove the hazardous waste.

Which word is closest in meaning to hazardous?

A. heavy
B. valuable
C. unusual
D. dangerous

Answer: D. dangerous

Hazardous means involving risk of harm, which is dangerous. The protective suits support that reading. Heavy, valuable, and unusual could describe waste, but none of them means risky.

Source: Merriam-Webster, “hazardous”.

Question 20 · Word Knowledge · Vocabulary Development

Which word is most nearly the OPPOSITE of scarce?

A. rare
B. expensive
C. hidden
D. abundant

Answer: D. abundant

Scarce means not plentiful, so its opposite is abundant, meaning plentiful. Rare is a synonym, the classic trap on antonym questions. Expensive may go along with scarcity, but it describes price, not amount. Hidden is about visibility.

Source: Merriam-Webster, “scarce”.

Question 21 · Word Knowledge · Vocabulary Development

Which word is most nearly the OPPOSITE of conceal?

A. hide
B. reveal
C. protect
D. repair

Answer: B. reveal

Conceal means to hide or keep out of sight, so the opposite is reveal. Hide is a synonym. Protect and repair are unrelated actions.

Source: Merriam-Webster, “conceal”.

Question 22 · Word Knowledge · Vocabulary Development

Which word is most nearly the OPPOSITE of expand?

A. contract
B. enlarge
C. release
D. repeat

Answer: A. contract

Expand means to increase in size. Its opposite is contract, to draw together and become smaller. Enlarge is a synonym. Release and repeat don't describe a change in size.

Source: Merriam-Webster, “contract” (verb).

Question 23 · Word Knowledge · Vocabulary Development

Choose the word that correctly completes the sentence.

Skipping breakfast did not seem to ___ her quiz score, which matched her usual result.

A. affect
B. effect
C. affects
D. effects

Answer: A. affect

The sentence needs a verb meaning “influence,” in its base form after “did not seem to.” That is affect. Effect is most often a noun; as a verb it means “to bring about,” which makes no sense here. Affects and effects are the wrong form after “to.”

Source: Merriam-Webster, “affect” (verb; affect vs. effect usage note).

Question 24 · Word Knowledge · Vocabulary Development

Choose the word that correctly completes the sentence.

The red scarf was a perfect ___ to her gray coat.

A. compliment
B. complacent
C. implement
D. complement

Answer: D. complement

A complement is something that completes or goes well with something else, which fits a scarf that suits a coat. A compliment is praise; the scarf isn't praising the coat. Complacent is an adjective meaning self-satisfied. An implement is a tool.

Source: Merriam-Webster, “complement”.

Question 25 · Word Knowledge · Vocabulary Development

Choose the word that correctly completes the sentence.

Honesty is a guiding ___ for the research team.

A. principle
B. principal
C. principally
D. principled

Answer: A. principle

The sentence needs a noun meaning a basic rule or belief: principle. Principal means “main” or refers to a head of a school; one memory trick is “the princiPAL is your pal.” Principally is an adverb and principled is an adjective, so neither fits after “a guiding.”

Source: Merriam-Webster, “principle”.

Reading Comprehension (Questions 26–50)

Five original passages, five questions each. Answer from what the passage says, not from what you already know about the topic.

Passage 1: Why Leaves Change Color

Original passage based on the sources linked below.

[1] In spring and summer, most tree leaves look green because of chlorophyll, the pigment that captures light energy for photosynthesis. During the growing season, the large amount of chlorophyll makes the green color dominate.

[2] Leaves also hold yellow and orange pigments called carotenoids. They are present all summer long, but the heavy green color masks them. They are there; you just can't see them yet.

[3] A signal for change comes with the season. As autumn nights grow longer, chlorophyll production slows and then stops, and the green fades. With the green gone, the carotenoids finally show. Because they were present the whole time, yellows and golds tend to appear fairly reliably from one year to the next.

[4] Reds and purples come from a different group of pigments, anthocyanins. Unlike carotenoids, most anthocyanins are made in the fall rather than stored from summer. Bright sunlight lets a leaf keep producing sugars during the day. Some of those sugars remain trapped in the leaves. Plenty of sugar plus plenty of light spurs anthocyanin production.

[5] That is why weather matters so much. According to the U.S. Forest Service, a run of warm, sunny days followed by cool but not freezing nights tends to produce the most brilliant displays. Temperature and moisture vary from year to year, so no two autumns look exactly alike.

Sources: USDA Forest Service, Why Leaves Change Color, pp. 1–2 (archived fact sheet SP-01-01).

Question 26 · Reading Comprehension · Reading for Information

According to the passage, which pigment makes leaves look green during the growing season?

A. carotenoids
B. chlorophyll
C. anthocyanins
D. a mix of carotenoids and anthocyanins

Answer: B. chlorophyll

Paragraph 1 says leaves look green “because of chlorophyll.” Carotenoids are yellow and orange (paragraph 2), and anthocyanins are red and purple (paragraph 4). The mix option combines two pigments that are not green.

Source: USDA Forest Service, Why Leaves Change Color, pp. 1–2 (archived fact sheet SP-01-01).

Question 27 · Reading Comprehension · Reading for Information

Which seasonal change does paragraph 3 connect with slowing chlorophyll production?

A. the first hard frost
B. nights growing longer in autumn
C. a drop in rainfall
D. leaves running out of carotenoids

Answer: B. nights growing longer in autumn

Paragraph 3 connects longer autumn nights with chlorophyll production slowing and stopping. Frost and rainfall aren't named there as the signal. Carotenoids don't run out; they become visible because they were present all along.

Source: USDA Forest Service, Why Leaves Change Color, pp. 1–2 (archived fact sheet SP-01-01).

Question 28 · Reading Comprehension · Application

Which statement best expresses the main idea of the passage?

A. Carotenoids are produced only in autumn, after the first frost ends the growing season.
B. Trees change color mainly to attract birds and other animals that spread their seeds.
C. Green chlorophyll fades in fall, other pigments show or form, and weather affects how bright they get.
D. Chlorophyll is the only pigment in leaves, so fall colors come from sunlight alone.

Answer: C. Green chlorophyll fades in fall, other pigments show or form, and weather affects how bright they get.

The passage walks through chlorophyll fading (paragraph 3), carotenoids showing (paragraphs 2–3), anthocyanins forming (paragraph 4), and weather's role (paragraph 5). Only the correct choice covers all of that. The carotenoid choice contradicts paragraph 2, which says carotenoids are present all summer. Seed-spreading animals never appear in the passage. The chlorophyll-only choice contradicts the whole passage, which names three kinds of pigment.

Source: USDA Forest Service, Why Leaves Change Color, pp. 1–2 (archived fact sheet SP-01-01).

Question 29 · Reading Comprehension · Application

In paragraph 2, the word masks most nearly means

A. creates
B. protects
C. hides
D. brightens

Answer: C. hides

The next sentence explains it: the carotenoids are there, “you just can't see them yet.” The green covers them up, so masks means hides. Creates is wrong because the pigments already exist. Protects and brightens aren't supported by the context.

Source: USDA Forest Service, Why Leaves Change Color, pp. 1–2 (archived fact sheet SP-01-01).

Question 30 · Reading Comprehension · Inference

Based on the passage, an autumn with mostly cloudy days would most likely produce

A. brighter yellows, because cloudy weather causes new carotenoids to form
B. no color change at all, because chlorophyll would stay in the leaves
C. more vivid reds, because cool, cloudy air traps even more sugar
D. less vivid reds, because less sunlight means fewer sugars for anthocyanins

Answer: D. less vivid reds, because less sunlight means fewer sugars for anthocyanins

Paragraph 4 says bright sunlight lets leaves keep producing sugars and that “plenty of sugar plus plenty of light” spurs anthocyanin production. Fewer sunny days means less of both, so reds should be less vivid. Carotenoids aren't formed by clouds; they were present all summer. Cloudy days do not rule out color change; paragraph 3 connects it with the seasonal change in night length. The “more vivid reds” choice ignores the missing sunlight.

Source: USDA Forest Service, Why Leaves Change Color, pp. 1–2 (archived fact sheet SP-01-01).

Passage 2: Noise and the Inner Ear

Original passage based on the sources linked below.

[1] Everyday sounds, from traffic to a humming refrigerator, are usually harmless. The trouble starts when a sound is too loud, even for a short time, or when it is both loud and long-lasting. Either situation can damage delicate structures deep inside the ear and cause noise-induced hearing loss.

[2] Hearing depends on a chain of events. Sound waves travel down the ear canal and make the eardrum vibrate. Three tiny bones in the middle ear pass those vibrations to the cochlea, a snail-shaped, fluid-filled part of the inner ear. There, sensory cells called hair cells ride a wave in the fluid and turn that motion into electrical signals, which the auditory nerve carries to the brain.

[3] Sound is measured in A-weighted decibels (dBA). The National Institute on Deafness and Other Communication Disorders (NIDCD) says sounds at or below 70 dBA are unlikely to cause hearing loss, even after long exposure. Long or repeated exposure to sounds at or above 85 dBA can cause hearing loss, and the louder the sound, the less time it takes. NIDCD lists normal conversation at about 60 to 70 dBA, motorcycles and dirt bikes at 80 to 110 dBA, and a fireworks show at 140 to 160 dBA.

[4] Most noise-induced hearing loss comes from damage to hair cells. Birds and amphibians can regrow these cells, but humans cannot. Once human hair cells die, they are gone for good.

[5] Because the damage usually builds up gradually, many people do not notice it at first. Over time, sounds may start to seem muffled, and conversations may become harder to follow. The good news is that this kind of hearing loss can be prevented: reducing the noise, wearing earplugs or earmuffs during loud activities, or simply moving away from the source all cut down on exposure.

Sources: NIDCD, Noise-Induced Hearing Loss (last updated April 16, 2025).

Question 31 · Reading Comprehension · Reading for Information

According to the passage, long or repeated exposure to sounds at what level can cause hearing loss?

A. 85 dBA or higher
B. 60 dBA or higher
C. 70 dBA or lower
D. 140 dBA only

Answer: A. 85 dBA or higher

Paragraph 3 states that long or repeated exposure to sounds at or above 85 dBA can cause hearing loss. 60 dBA is the low end of normal conversation. 70 dBA or lower is the range the passage calls unlikely to cause loss. 140 dBA is a fireworks show, and the passage never says only that level is harmful.

Source: NIDCD, Noise-Induced Hearing Loss (last updated April 16, 2025).

Question 32 · Reading Comprehension · Reading for Information

Which cells does the passage say turn sound vibrations into electrical signals?

A. cells of the eardrum
B. the three bones of the middle ear
C. hair cells in the cochlea
D. cells of the auditory nerve

Answer: C. hair cells in the cochlea

Paragraph 2 says hair cells in the cochlea turn the motion into electrical signals. The eardrum vibrates and the middle-ear bones pass the vibrations along, but neither makes electrical signals. The auditory nerve carries the signals to the brain after the hair cells create them.

Source: NIDCD, Noise-Induced Hearing Loss (last updated April 16, 2025).

Question 33 · Reading Comprehension · Application

Using the passage's information, which situation poses the greatest risk to hearing?

A. attending a fireworks show
B. having a long conversation in a quiet café
C. reading in a library
D. listening to a humming refrigerator

Answer: A. attending a fireworks show

Paragraph 3 lists a fireworks show at 140 to 160 dBA, far above the 85 dBA level linked to hearing loss. Normal conversation is 60 to 70 dBA, which the passage calls unlikely to cause loss. A library and a refrigerator are the kinds of everyday sounds paragraph 1 calls usually harmless.

Source: NIDCD, Noise-Induced Hearing Loss (last updated April 16, 2025).

Question 34 · Reading Comprehension · Application

The author's main purpose in the passage is to

A. argue that concerts, fireworks, and other loud entertainment should be banned
B. explain how loud sound damages hearing and how the damage can be prevented
C. compare how hearing works in humans with how it works in birds
D. describe new medical treatments that regrow damaged hair cells in humans

Answer: B. explain how loud sound damages hearing and how the damage can be prevented

The passage explains how hearing works, what sound levels are risky, why the damage lasts, and how to prevent it. The banning choice overstates the tone; the passage recommends protection, not bans. Birds come up in one sentence only, so a comparison isn't the purpose. The treatment choice contradicts paragraph 4, which says human hair cells don't grow back.

Source: NIDCD, Noise-Induced Hearing Loss (last updated April 16, 2025).

Question 35 · Reading Comprehension · Inference

Based on paragraphs 4 and 5, which conclusion is best supported?

A. People usually notice noise damage right away, so they can stop it early.
B. Protecting hearing ahead of time matters because noise damage to hair cells cannot be undone.
C. Human hair cells grow back within a few weeks once the noise stops.
D. Any sound below 85 dBA will eventually cause some hearing damage.

Answer: B. Protecting hearing ahead of time matters because noise damage to hair cells cannot be undone.

Paragraph 4 says human hair cells that die are “gone for good,” and paragraph 5 says the damage can be prevented. Put together, prevention matters because repair isn't possible. Paragraph 5 says many people don't notice the damage at first. Paragraph 4 says human hair cells don't regrow. Paragraph 3 says sounds at or below 70 dBA are unlikely to cause loss, so the claim about any sound below 85 dBA is wrong.

Source: NIDCD, Noise-Induced Hearing Loss (last updated April 16, 2025).

Passage 3: How a Phone Knows Where It Is

Original passage based on the sources linked below.

[1] The Global Positioning System (GPS) is owned by the U.S. government and has three parts: satellites in space, stations on the ground that monitor and control them, and receivers, like the one in a phone, that use the satellites' signals.

[2] GPS satellites travel in medium Earth orbit, about 20,200 kilometers (12,550 miles) above the surface, and each one circles the planet twice a day. The United States commits to keeping at least 24 working GPS satellites available 95 percent of the time. The satellites are arranged in six orbital planes, a constellation designed so that a receiver can see at least four satellites from almost anywhere on Earth.

[3] Each satellite constantly broadcasts radio signals that include its location, its status, and a precise time from atomic clocks on board. The signals travel at the speed of light. A receiver notes exactly when each signal arrives. The difference between the time a signal was sent and the time it was received is its travel time, and distance equals speed multiplied by time. By working out its distance from several satellites whose positions are known, the receiver can calculate where it is.

[4] Accuracy depends on more than the satellites. According to GPS.gov, a GPS-enabled smartphone is typically accurate to within about 4.9 meters (16 feet) under open sky, but accuracy gets worse near buildings, bridges, and trees. Common causes of error include signals being blocked, using a device indoors or underground, and signals bouncing off buildings or walls before they reach the receiver.

Sources: GPS.gov, Space Segment; GPS.gov, GPS Accuracy: smartphone accuracy and common causes of error; GPS.gov, How GPS Works (archived poster: signal timing and distance calculation); NOAA, What is GPS?.

Question 36 · Reading Comprehension · Reading for Information

According to the passage, what information do GPS satellite signals include?

A. the satellite's location, status, and a precise time
B. the receiver's street address and nearest cross street
C. a map of nearby roads and landmarks
D. the local weather and temperature at the receiver

Answer: A. the satellite's location, status, and a precise time

Paragraph 3 says each satellite broadcasts its location, its status, and a precise time from onboard atomic clocks. The receiver works out its own position; the satellites don't send addresses, maps, or weather.

Source: GPS.gov, How GPS Works (archived poster: signal timing and distance calculation).

Question 37 · Reading Comprehension · Reading for Information

How often does each GPS satellite circle Earth?

A. once a day
B. twice a day
C. 24 times a day
D. once every 95 days

Answer: B. twice a day

Paragraph 2 says each satellite circles the planet twice a day. The other choices borrow numbers from the same paragraph: 24 is the minimum number of working satellites, and 95 is the percent of time that commitment covers.

Source: GPS.gov, Space Segment.

Question 38 · Reading Comprehension · Application

In paragraph 2, the word constellation most nearly means

A. a pattern of stars
B. a ground control station
C. a single orbit
D. an arranged group of satellites

Answer: D. an arranged group of satellites

In everyday speech a constellation is a pattern of stars, and that's the trap. In this paragraph, the word refers to the satellites “arranged in six orbital planes,” so it means an arranged group of satellites. A ground station is a different part of the system (paragraph 1), and six planes is more than a single orbit.

Source: GPS.gov, Space Segment.

Question 39 · Reading Comprehension · Application

A hiker's phone shows her location jumping around while she walks through thick forest at the bottom of a narrow canyon. Based on the passage, what is the most likely reason?

A. The satellites stop broadcasting when they pass over forests.
B. Her phone can see too many satellites at once.
C. Trees and canyon walls are blocking or reflecting the satellite signals.
D. Atomic clocks stop working in cold weather.

Answer: C. Trees and canyon walls are blocking or reflecting the satellite signals.

Paragraph 4 says accuracy worsens near trees and that blocked signals and signals bouncing off walls cause errors. A canyon under thick forest has both problems. Nothing in the passage says satellites stop broadcasting, and seeing more satellites is the design goal, not a problem. Clock failure in cold weather is never mentioned.

Source: GPS.gov, GPS Accuracy: smartphone accuracy and common causes of error.

Question 40 · Reading Comprehension · Inference

Based on paragraph 3, why do the satellites' clocks need to be so precise?

A. The receiver turns signal travel time into distance, so a small timing error would throw off the calculated position.
B. The clocks control the satellites' speed so each one circles Earth exactly twice a day.
C. The signals travel much more slowly than light, so they need extra timing information.
D. The phone needs the satellite's clock so it can display the correct local time zone.

Answer: A. The receiver turns signal travel time into distance, so a small timing error would throw off the calculated position.

Paragraph 3 explains that distance equals speed multiplied by travel time, and that the receiver finds its position from those distances. If the time is off, the distance and position are off too. The passage never links the clocks to the satellites' orbits. It says the signals travel at the speed of light, not slower. Time zones aren't mentioned.

Source: GPS.gov, How GPS Works (archived poster: signal timing and distance calculation).

Passage 4: The Nurse Who Drew the Numbers

Original passage based on the sources linked below.

[1] Florence Nightingale is often remembered as a nurse carrying a lamp through hospital wards at night. During the Crimean War (1853–1856), she and a team of nurses ran hospitals for wounded British soldiers evacuated from the fighting. What she found there went far beyond bandages and bedside care.

[2] The hospitals were crowded and unsanitary. Careful records of how soldiers died told a shocking story: more soldiers were killed by preventable diseases, spread by unsanitary conditions, than by battlefield wounds.

[3] Numbers alone rarely change minds, so Nightingale worked to make these impossible to ignore. Working with the statistician William Farr, she presented the data in striking diagrams. In her best-known chart, each wedge stood for one month, and its colored areas compared mortality from different causes. Blue areas represented deaths from preventable disease, red areas deaths from wounds, and black areas deaths from other causes. One glance showed how large the blue areas were.

[4] Nightingale did not invent this type of chart, but she used it with unusual force. Her aim was to convince the British army and government that military hospitals needed sweeping sanitary reform. Her charts also showed that death rates fell after sanitary improvements were made.

[5] Her statistical work earned recognition in her own time. In 1858 she became the first woman elected a fellow of the Statistical Society of London, now the Royal Statistical Society. Her diagrams are still discussed as an early example of using pictures of data to argue for change.

Sources: Science Museum, Florence Nightingale: The pioneer statistician; The Nightingale Society, The real goods and the oversell; Science Museum collection, Nightingale mortality diagram (original graphic, month/cause legend).

Question 41 · Reading Comprehension · Reading for Information

According to the passage, what did the records show about how soldiers died?

A. Most soldiers died from wounds received in battle.
B. More soldiers died from preventable diseases than from battlefield wounds.
C. Deaths were spread evenly among all causes.
D. Most deaths happened after sanitary improvements were made.

Answer: B. More soldiers died from preventable diseases than from battlefield wounds.

Paragraph 2 says more soldiers were killed by preventable diseases than by battlefield wounds. The wounds choice reverses that finding. The charts' large blue areas (paragraph 3) show the causes were not even. The passage reports a fall in death rates after improvements, not that most deaths came afterward.

Source: Science Museum, Florence Nightingale: The pioneer statistician.

Question 42 · Reading Comprehension · Reading for Information

In Nightingale's best-known chart, what did the colored areas within each month's wedge represent?

A. how many nurses worked that month
B. how many hospitals were open
C. mortality from different causes during that month
D. how long the war had lasted

Answer: C. mortality from different causes during that month

Paragraph 3 explains that each wedge stood for one month and its colored areas compared causes of mortality: preventable disease, wounds, and other causes. Nurses, hospital counts, and the length of the war aren't what those colored areas represented.

Source: Science Museum, Florence Nightingale: The pioneer statistician.

Question 43 · Reading Comprehension · Application

The author's main purpose in the passage is to

A. show how Nightingale used data and diagrams to push for hospital reform
B. prove that Nightingale invented the polar area chart
C. describe the daily tasks of nurses in wartime hospitals
D. compare British and French army hospitals

Answer: A. show how Nightingale used data and diagrams to push for hospital reform

Most of the passage is about her records, her diagrams, and her goal of reform. The invention choice contradicts paragraph 4, which says she did not invent this type of chart. Daily nursing tasks are only brushed aside in paragraph 1, and French hospitals never appear.

Source: Science Museum, Florence Nightingale: The pioneer statistician; The Nightingale Society, The real goods and the oversell.

Question 44 · Reading Comprehension · Application

In paragraph 4, the word sweeping most nearly means

A. cleaning
B. quick and careless
C. temporary
D. wide-ranging

Answer: D. wide-ranging

“Sweeping sanitary reform” means reform that reaches across the whole system, so wide-ranging fits. Cleaning is the literal meaning of sweep, and it's a tempting trap in a sentence about sanitation. But the word describes the size of the reform, not a broom. Quick and careless and temporary don't match Nightingale's goal of lasting change.

Source: Science Museum, Florence Nightingale: The pioneer statistician.

Question 45 · Reading Comprehension · Inference

Based on the passage, why were the diagrams likely more persuasive than a table of numbers?

A. They packed in more monthly numbers than any printed table could hold.
B. They were printed in the British army's official colors to look authoritative.
C. They let readers see the size of the preventable-disease problem at a glance.
D. They left out the deaths from wounds so the disease numbers stood out more.

Answer: C. They let readers see the size of the preventable-disease problem at a glance.

Paragraph 3 says numbers alone rarely change minds and that “one glance” at the chart showed how large the blue areas were. That supports the at-a-glance answer. The passage never says the diagrams held more data or used official colors. The chart did include deaths from wounds, shown in red.

Source: Science Museum, Florence Nightingale: The pioneer statistician.

Passage 5: A Library Tries a New Room Policy

Original fictional passage for this practice set.

[1] At a college library, students kept complaining that the online system showed every group study room as booked, even when several rooms sat empty. Staff suspected that some groups reserved rooms and never showed up, while others stayed far longer than they needed. Before changing anything, staff spent two weeks recording how the rooms were actually used.

[2] The library then began a four-week trial with two new rules. First, a group could reserve a room for no more than two hours at a time, so that one group could not hold a room for an excessive period. Second, a group had to check in at the front desk within 10 minutes of its reservation's start time. If no one checked in by then, staff could release the room to another group.

[3] During the trial, the share of available room-hours that were actually used rose compared with the two-week baseline. Staff were careful not to overstate that result. The trial happened to overlap with the college's exam period, when students tend to study more, so some of the increase might have happened with or without the new rules.

[4] In their report, staff called the results promising but not conclusive. They also noted that room-hours measure how much the rooms were used, not how many different students got a turn. They recommended repeating the comparison during a similar part of a later semester before making the policy permanent.

Question 46 · Reading Comprehension · Reading for Information

Under the trial rules, when could staff release a reserved room to another group?

A. after a group had used the room for at least one full hour
B. whenever the online system showed the room as booked for the day
C. when no one had checked in within 10 minutes of the reservation's start time
D. when a group had reserved the room for more than two hours in a row

Answer: C. when no one had checked in within 10 minutes of the reservation's start time

Paragraph 2 says that if no one checked in within 10 minutes of the start time, staff could release the room. One hour of use isn't a release condition. The online system showing “booked” was the original problem, not a rule. And under the trial a group couldn't reserve more than two hours in the first place.

Source: Passage 5 above (original fictional passage).

Question 47 · Reading Comprehension · Reading for Information

What reason does the passage give for the two-hour limit?

A. to give library staff enough time to clean each room between groups
B. to keep one group from holding a room for an excessive period
C. to lower the cost of heating and lighting the rooms
D. to make the online booking system load and run faster

Answer: B. to keep one group from holding a room for an excessive period

Paragraph 2 states the reason directly: so that one group could not hold a room for an excessive period. Cleaning, cost, and system speed are never mentioned.

Source: Passage 5 above (original fictional passage).

Question 48 · Reading Comprehension · Application

A group reserved a room for 3:00 p.m. It is now 3:12 p.m., and no one from the group has checked in. Under the trial rules, what may staff do?

A. hold the room for the group until 5:00 p.m.
B. extend the reservation to three hours
C. release the room to another group
D. cancel all of the group's future reservations

Answer: C. release the room to another group

The 10-minute check-in window ended at 3:10 p.m., and no one checked in, so staff may release the room. Holding it until 5:00 ignores the rule. A three-hour reservation breaks the two-hour limit. The passage describes no penalty for future reservations.

Source: Passage 5 above (original fictional passage).

Question 49 · Reading Comprehension · Application

Which statement best summarizes the passage?

A. A library proved that time limits always increase room use.
B. Students used the study rooms less during the exam period.
C. The library replaced its online booking system with a paper sign-up sheet.
D. A library tested new room rules and found encouraging but not yet conclusive results.

Answer: D. A library tested new room rules and found encouraging but not yet conclusive results.

The passage describes a trial, a rise in room use, and staff calling the results “promising but not conclusive.” The “proved … always” choice overstates what staff concluded. Room use rose during the trial, which overlapped the exam period, so the second choice contradicts the passage. No paper sign-up sheet is mentioned.

Source: Passage 5 above (original fictional passage).

Question 50 · Reading Comprehension · Inference

Why did staff most likely recommend repeating the comparison during a similar part of a later semester?

A. so that heavy studying during exams would not be mistaken for an effect of the new rules
B. because the new rules turned out to be too popular with students to keep
C. because room-hours cannot be measured accurately during exam weeks
D. so that more students would get used to checking in at the front desk

Answer: A. so that heavy studying during exams would not be mistaken for an effect of the new rules

Paragraph 3 says the trial overlapped the exam period, when students study more, so part of the increase might have happened anyway. Comparing similar periods helps reduce exam-season demand as an alternative explanation. Nothing says the rules were too popular, and room-hours clearly were measured during exams. More check-ins isn't the purpose of a comparison.

Source: Passage 5 above (original fictional passage).

Math practice questions

Questions 51–90. The NEX testing platform has a built-in calculator (NLN Technical Manual, §4.2), so practice with a basic four-function calculator, and check your setup as well as your arithmetic. Optional count-based pacing estimate: about 53 minutes (method and limits). Numbers that appear in health settings are for arithmetic practice only; they are not dosing or care instructions.

Numbers and Operations (Questions 51–62)

Question 51 · Numbers and Operations · Computation

What is 2/3 + 3/4?

A. 5/7
B. 1 5/12
C. 5/12
D. 1/2

Answer: B. 1 5/12

Rewrite both fractions with the common denominator 12: 2/3 = 8/12 and 3/4 = 9/12. Then 8/12 + 9/12 = 17/12 = 1 5/12. The answer 5/7 comes from adding the tops and the bottoms separately, which is not the rule for adding fractions. 5/12 uses the common denominator but forgets to change the numerators. 1/2 is what you get by multiplying (2/3 × 3/4 = 6/12) instead of adding.

Source: OpenStax, Prealgebra 2e, §4.5 Add and Subtract Fractions with Different Denominators.

Question 52 · Numbers and Operations · Computation

What is 7.2 ÷ 0.06?

A. 1.2
B. 12
C. 120
D. 1,200

Answer: C. 120

Multiply both numbers by 100 so the divisor becomes a whole number: 7.2 ÷ 0.06 = 720 ÷ 6 = 120. Check: 0.06 × 120 = 7.2. The answers 1.2, 12, and 1,200 all use the right digits but move the decimal point the wrong number of places. A quick size check helps: dividing by a number much smaller than 1 makes the result bigger than 7.2.

Source: OpenStax, Prealgebra 2e, §5.2 Decimal Operations.

Question 53 · Numbers and Operations · Computation

Which percent is equal to 7/8?

A. 78%
B. 87.5%
C. 8.75%
D. 0.875%

Answer: B. 87.5%

Divide: 7 ÷ 8 = 0.875. To change a decimal to a percent, multiply by 100: 87.5%. The answer 78% just reuses the digits 7 and 8. 8.75% and 0.875% put the decimal point in the wrong place; 0.875% forgets to multiply by 100 at all.

Source: OpenStax, Prealgebra 2e, §6.1 Understand Percent.

Question 54 · Numbers and Operations · Computation

What is the value of −3 + 4 × (6 − 8)² ÷ 2?

A. −11
B. 2
C. 5
D. 29

Answer: C. 5

Work in order: parentheses, then exponents, then multiplication and division from left to right, then addition. (6 − 8) = −2. Next, (−2)² = 4. Then 4 × 4 = 16, and 16 ÷ 2 = 8. Finally, −3 + 8 = 5. The answer −11 treats (−2)² as −4, but a negative number squared is positive. The answer 2 adds −3 + 4 before multiplying. The answer 29 multiplies 4 × (−2) before squaring.

Source: OpenStax, Prealgebra 2e, §2.1 Use the Language of Algebra (order of operations).

Question 55 · Numbers and Operations · Problem Solving

A jacket costs $80. It is marked 25% off, and then a 5% sales tax is added to the sale price. What is the total cost?

A. $60.00
B. $64.00
C. $63.00
D. $84.00

Answer: C. $63.00

Take the discount first: 25% of $80 is $20, so the sale price is $60. Then add tax on the sale price: 5% of $60 is $3, for a total of $63.00. $60.00 forgets the tax. $64.00 subtracts 25% − 5% = 20% in one step, but tax is added to the discounted price, not netted against the discount. $84.00 adds the tax and skips the discount.

Source: OpenStax, Prealgebra 2e, §6.3 Solve Sales Tax, Commission, and Discount Applications.

Question 56 · Numbers and Operations · Problem Solving

Weekly attendance at a study group rose from 240 people to 300 people. What was the percent increase?

A. 20%
B. 60%
C. 125%
D. 25%

Answer: D. 25%

Percent increase = amount of change ÷ original amount. The change is 300 − 240 = 60, and 60 ÷ 240 = 0.25, or 25%. 20% divides by the new amount (60 ÷ 300) instead of the original. 60% treats the raw change as a percent. 125% is the new amount as a percent of the old (300 ÷ 240), not the increase.

Source: OpenStax, Prealgebra 2e, §6.2 Solve General Applications of Percent.

Question 57 · Numbers and Operations · Problem Solving

A club splits 64 donated books between two schools in a 3 : 5 ratio. How many books does the school with the smaller share receive?

A. 24
B. 32
C. 38.4
D. 40

Answer: A. 24

A 3 : 5 ratio has 3 + 5 = 8 equal parts. Each part is 64 ÷ 8 = 8 books, so the smaller share is 3 × 8 = 24. 40 is the larger share (5 × 8). 32 splits the books evenly and ignores the ratio. 38.4 treats 3 : 5 as the fraction 3/5 of the total, which isn't what a ratio means, and a fraction of a book is a warning sign.

Source: OpenStax, Prealgebra 2e, §5.6 Ratios and Rate.

Question 58 · Numbers and Operations · Problem Solving

After a 20% discount, a textbook costs $36. What was the original price?

A. $28.80
B. $43.20
C. $45.00
D. $56.00

Answer: C. $45.00

After a 20% discount you pay 80% of the original, so 0.80 × original = $36. Divide: $36 ÷ 0.80 = $45.00. Check: 20% of $45 is $9, and $45 − $9 = $36. $43.20 adds 20% of the sale price, but the discount was 20% of the original, a larger number. $28.80 takes another 20% off. $56.00 adds $20 as if the discount were a dollar amount.

Source: OpenStax, Prealgebra 2e, §6.3 Solve Sales Tax, Commission, and Discount Applications.

Question 59 · Numbers and Operations · Problem Solving

A case holds 48 bottles of water. On Monday, 3/4 of the bottles were used. On Tuesday, 1/3 of the remaining bottles were used. How many bottles are left?

A. 4
B. 12
C. 32
D. 8

Answer: D. 8

Monday: 3/4 of 48 is 36 bottles used, leaving 12. Tuesday: 1/3 of those 12 is 4 bottles used, leaving 8. The answer 4 is how many were used on Tuesday, not how many are left. 12 stops after Monday. 32 takes 1/3 of the full case (16) and skips Monday entirely.

Source: OpenStax, Prealgebra 2e, §4.5 Add and Subtract Fractions with Different Denominators.

Question 60 · Numbers and Operations · Problem Solving

Which number is largest?

A. 5/8
B. 0.605
C. 61%
D. 3/5

Answer: A. 5/8

Convert everything to decimals: 5/8 = 0.625, 0.605 stays 0.605, 61% = 0.61, and 3/5 = 0.6. The largest is 0.625, which is 5/8. It's easy to be pulled toward 0.605 because it has the most digits, or toward 61% because 61 looks big. Compare place value, not the length of the number.

Source: OpenStax, Prealgebra 2e, §6.1 Understand Percent.

Question 61 · Numbers and Operations · Problem Solving

Which size of the same brand of oatmeal costs the least per ounce?

A. 12-ounce box for $3.60
B. 16-ounce box for $4.64
C. 32-ounce box for $8.96
D. 20-ounce box for $5.40

Answer: D. 20-ounce box for $5.40

Divide price by ounces for each box: $3.60 ÷ 12 = $0.30, $4.64 ÷ 16 = $0.29, $5.40 ÷ 20 = $0.27, and $8.96 ÷ 32 = $0.28. The 20-ounce box has the lowest cost per ounce. The 32-ounce box is the tempting guess, since bigger packages are often cheaper per unit, but here it costs a cent more per ounce.

Source: OpenStax, Prealgebra 2e, §5.6 Ratios and Rate.

Question 62 · Numbers and Operations · Problem Solving

At 6 a.m. the temperature was −4°C. By noon it was 9°C. By how many degrees did the temperature rise?

A. 5 degrees
B. 9 degrees
C. 13 degrees
D. −13 degrees

Answer: C. 13 degrees

The rise is the final temperature minus the starting temperature: 9 − (−4) = 9 + 4 = 13 degrees. You can also count on a number line: 4 degrees up to 0, then 9 more. 5 degrees ignores the negative sign (9 − 4). 9 degrees is the final temperature, not the change. −13 subtracts in the wrong order; a rise is positive.

Source: OpenStax, Prealgebra 2e, §3.3 Subtract Integers.

Measurement (Questions 63–76)

Question 63 · Measurement · Computation

How many grams are in 2,500 milligrams?

A. 0.25 g
B. 2.5 g
C. 25 g
D. 2,500,000 g

Answer: B. 2.5 g

Milli- means one-thousandth, so 1 gram = 1,000 milligrams. To go from milligrams to grams, divide by 1,000: 2,500 ÷ 1,000 = 2.5 g. 0.25 g and 25 g move the decimal the wrong number of places. 2,500,000 g multiplies instead of dividing, but grams are the larger unit, so the number must get smaller.

Source: NIST, Metric (SI) Prefixes: kilo, centi, and milli; OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 64 · Measurement · Computation

How many milliliters are in 0.75 liter?

A. 7.5 mL
B. 750 mL
C. 75 mL
D. 7,500 mL

Answer: B. 750 mL

1 liter = 1,000 milliliters, so multiply: 0.75 × 1,000 = 750 mL. The other choices shift the decimal point too few or too many places. A sense check: 0.75 liter is three-quarters of a liter, and three-quarters of 1,000 is 750.

Source: NIST, Metric (SI) Prefixes: kilo, centi, and milli; OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 65 · Measurement · Computation

A person is 1.82 meters tall. What is this height in centimeters?

A. 18.2 cm
B. 1,820 cm
C. 0.0182 cm
D. 182 cm

Answer: D. 182 cm

1 meter = 100 centimeters, so 1.82 × 100 = 182 cm. 1,820 cm multiplies by 1,000 (the meter-to-millimeter factor). 18.2 cm multiplies by 10. 0.0182 cm divides instead of multiplying; centimeters are smaller units, so the number should get bigger.

Source: NIST, Metric (SI) Prefixes: kilo, centi, and milli; OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 66 · Measurement · Computation

How many inches are in 5 feet 4 inches? (1 foot = 12 inches)

A. 9 inches
B. 54 inches
C. 60 inches
D. 64 inches

Answer: D. 64 inches

Convert the feet, then add the extra inches: 5 × 12 = 60, and 60 + 4 = 64 inches. 54 inches treats a foot as 10 inches. 60 inches forgets the extra 4. 9 inches just adds 5 + 4 without converting.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 67 · Measurement · Computation

What is 3:45 p.m. in 24-hour time?

A. 0345
B. 1545
C. 1345
D. 1645

Answer: B. 1545

For p.m. times from 1:00 to 11:59, add 12 to the hour: 3 + 12 = 15, so 3:45 p.m. is 1545. 0345 is 3:45 a.m. 1345 adds 10 instead of 12, and 1645 adds 13.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 68 · Measurement · Problem Solving

A bookshelf is 64 inches tall. Using 1 inch = 2.54 centimeters, how tall is it in centimeters?

A. 16.256 cm
B. 25.2 cm
C. 66.54 cm
D. 162.56 cm

Answer: D. 162.56 cm

Each inch is 2.54 cm, so multiply: 64 × 2.54 = 162.56 cm. Centimeters are smaller than inches, so the number must get bigger. 25.2 cm divides instead (64 ÷ 2.54 is about 25.2). 66.54 cm adds the conversion factor. 16.256 cm has the right digits with the decimal point in the wrong place.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement: conversion factors.

Question 69 · Measurement · Problem Solving

A patient's weight is recorded as 154 pounds. Using 1 kilogram = 2.2 pounds, what is the weight in kilograms?

A. 77 kg
B. 70 kg
C. 151.8 kg
D. 338.8 kg

Answer: B. 70 kg

A kilogram is heavier than a pound, so the number of kilograms must be smaller: 154 ÷ 2.2 = 70. Check: 70 × 2.2 = 154. 338.8 kg multiplies by 2.2 instead of dividing. 151.8 kg subtracts 2.2 as if it were an amount. 77 kg halves the weight, a shortcut that isn't the conversion given. The factor 2.2 is a rounded value, which is why the question states it.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement: conversion factors.

Question 70 · Measurement · Problem Solving

A stock salt solution contains 250 milligrams of salt in every 5 milliliters. How many milliliters of the solution contain 150 milligrams of salt?

A. 0.6 mL
B. 3 mL
C. 8.3 mL
D. 30 mL

Answer: B. 3 mL

Set up a proportion: 250 mg / 5 mL = 150 mg / x mL. The solution holds 50 mg per mL (250 ÷ 5), so 150 ÷ 50 = 3 mL. 0.6 mL is 150 ÷ 250, which is only part of the setup. 8.3 mL flips the ratio (250 ÷ 150 × 5). 30 mL divides 150 by 5 as if each milliliter held 5 mg.

Source: OpenStax, Prealgebra 2e, §6.5 Solve Proportions and their Applications.

Question 71 · Measurement · Problem Solving

A lab pump moves liquid at 125 milliliters per hour. How long will it take to move 1 liter?

A. 8 hours
B. 0.125 hours
C. 0.8 hours
D. 80 hours

Answer: A. 8 hours

Convert first: 1 liter = 1,000 mL. Then time = amount ÷ rate = 1,000 ÷ 125 = 8 hours. 0.125 hours divides the rate by the amount, which is backward. 0.8 hours uses 100 mL in a liter, and 80 hours uses 10,000 mL. Both are conversion errors.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement; OpenStax, Prealgebra 2e, §5.6 Ratios and Rate.

Question 72 · Measurement · Problem Solving

A night shift starts at 2230 and ends at 0615 the next morning. Assume there is no clock change overnight. How long is the shift?

A. 7 hours 45 minutes
B. 6 hours 15 minutes
C. 8 hours 15 minutes
D. 16 hours 15 minutes

Answer: A. 7 hours 45 minutes

Split the shift at midnight. From 2230 to 2400 is 1 hour 30 minutes. From 0000 to 0615 is 6 hours 15 minutes. Together: 7 hours 45 minutes. 16 hours 15 minutes comes from subtracting 0615 from 2230, which measures the wrong stretch of time. 6 hours 15 minutes counts only the hours after midnight. 8 hours 15 minutes miscounts the time before midnight.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 73 · Measurement · Problem Solving

Use °C = (°F − 32) × 5/9. What is 98.6°F in degrees Celsius?

A. 22.8°C
B. 66.6°C
C. 37.0°C
D. 119.9°C

Answer: C. 37.0°C

Subtract first, because of the parentheses: 98.6 − 32 = 66.6. Then multiply by 5/9: 66.6 × 5 ÷ 9 = 37.0°C. 22.8°C multiplies 98.6 by 5/9 before subtracting 32. 66.6°C stops after the first step. 119.9°C multiplies by 9/5, the factor for going from Celsius to Fahrenheit.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 74 · Measurement · Problem Solving

On a map, 1 centimeter represents 25 kilometers. Two towns are 3.4 centimeters apart on the map. What is the actual distance between them?

A. 7.4 km
B. 28.4 km
C. 850 km
D. 85 km

Answer: D. 85 km

Each map centimeter stands for 25 km, so multiply: 3.4 × 25 = 85 km. 7.4 km divides 25 by 3.4. 28.4 km adds the two numbers. 850 km puts the decimal point in the wrong place; 3 cm alone would be 75 km, so the answer must be close to that.

Source: OpenStax, Prealgebra 2e, §6.5 Solve Proportions and their Applications.

Question 75 · Measurement · Problem Solving

A rectangular floor is 12 feet long and 9.5 feet wide. Flooring costs $3 per square foot. Using area = length × width, how much will flooring cost for the whole floor?

A. $64.50
B. $114
C. $129
D. $342

Answer: D. $342

Area = 12 × 9.5 = 114 square feet. Cost = 114 × $3 = $342. $114 finds the area but forgets the price. $129 uses the perimeter (2 × 12 + 2 × 9.5 = 43 feet) instead of the area; perimeter measures the edge, not the surface you cover. $64.50 adds the two sides and multiplies by 3.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement.

Question 76 · Measurement · Problem Solving

A pitcher holds 1.8 liters. Using 1 fluid ounce ≈ 30 milliliters, what volume is this in 8-fluid-ounce cups, including a partial cup?

A. 7.5 cups
B. 6 cups
C. 60 cups
D. 225 cups

Answer: A. 7.5 cups

Chain the conversions: 1.8 L = 1,800 mL. Then 1,800 ÷ 30 = 60 fluid ounces, and 60 ÷ 8 = 7.5 cups. 60 cups stops at fluid ounces. 225 cups divides 1,800 mL by 8 without converting to ounces. 6 cups would require treating each cup as 300 mL rather than 8 × 30 = 240 mL. The factor 30 mL is an approximation, which is why the question gives it.

Source: OpenStax, Prealgebra 2e, §7.5 Systems of Measurement: conversion factors.

Algebra (Questions 77–83)

Question 77 · Algebra · Computation

Solve for x: 5x − 7 = 18

A. x = 5
B. x = 2.2
C. x = 3.6
D. x = 25

Answer: A. x = 5

Undo the subtraction first by adding 7 to both sides: 5x = 25. Then divide both sides by 5: x = 5. Check: 5(5) − 7 = 18. x = 2.2 subtracts 7 instead of adding it (11 ÷ 5). x = 3.6 ignores the −7 (18 ÷ 5). x = 25 forgets the last step of dividing by 5.

Source: OpenStax, Prealgebra 2e, §8.3 Solve Equations with Variables and Constants on Both Sides.

Question 78 · Algebra · Computation

What is the value of 3a² − 2b when a = 4 and b = 5?

A. 14
B. 38
C. 58
D. 134

Answer: B. 38

Square first: a² = 16. Then 3 × 16 = 48 and 2 × 5 = 10, so 48 − 10 = 38. 14 treats a² as 2a (3 × 8 − 10). 58 adds 2b instead of subtracting. 134 squares 3a instead of just a: (3 × 4)² − 10 = 144 − 10.

Source: OpenStax, Prealgebra 2e, §2.1 Use the Language of Algebra (order of operations).

Question 79 · Algebra · Computation

Solve: −2x + 3 > 11

A. x > −4
B. x > 4
C. x < −7
D. x < −4

Answer: D. x < −4

Subtract 3 from both sides: −2x > 8. Divide both sides by −2, and flip the inequality sign because you divided by a negative number: x < −4. Check with x = −5: −2(−5) + 3 = 13, which is greater than 11. x > −4 forgets to flip the sign. x > 4 loses the negative. x < −7 adds 3 instead of subtracting it.

Source: OpenStax, Elementary Algebra 2e, §2.7 Solve Linear Inequalities.

Question 80 · Algebra · Problem Solving

A gym charges a one-time $25 joining fee plus $12 per month. Dana has paid $121 in total. For how many months has she been a member?

A. 8 months
B. 3 months
C. 10 months
D. 12 months

Answer: A. 8 months

Write the equation 25 + 12m = 121. Subtract the fee: 12m = 96. Divide: m = 8. Check: 25 + 12 × 8 = 121. The other choices come from setups that don't give whole numbers: 121 ÷ 12 is about 10 (ignores the fee), 146 ÷ 12 is about 12 (adds the fee), and 121 ÷ 37 is about 3 (adds the fee to the monthly price).

Source: OpenStax, Prealgebra 2e, §8.3 Solve Equations with Variables and Constants on Both Sides.

Question 81 · Algebra · Problem Solving

A paint mix uses 15 mL of blue paint for every 20 mL of white paint. How many milliliters of blue paint go with 12 mL of white paint?

A. 7 mL
B. 16 mL
C. 9 mL
D. 180 mL

Answer: C. 9 mL

Set up blue/white = 15/20 = x/12. Simplify 15/20 to 3/4, then x = 12 × 3/4 = 9 mL. 16 mL flips the ratio (12 × 20 ÷ 15). 7 mL subtracts the 5 mL difference from 12, but ratios work by multiplying, not by keeping a fixed difference. 180 mL multiplies 12 × 15 and never divides by 20.

Source: OpenStax, Prealgebra 2e, §6.5 Solve Proportions and their Applications.

Question 82 · Algebra · Problem Solving

A rectangle is (3x + 4) centimeters long and x centimeters wide. Its perimeter is 40 centimeters. Use P = 2L + 2W, where L is length and W is width. What is x?

A. 4
B. 4.5
C. 5
D. 9

Answer: A. 4

Perimeter = 2 × length + 2 × width = 2(3x + 4) + 2x = 6x + 8 + 2x = 8x + 8. Set 8x + 8 = 40, so 8x = 32 and x = 4. Check: the length is 16 and the width is 4, and 2(16 + 4) = 40. 4.5 forgets to multiply the 4 by 2 (8x + 4 = 40). 5 drops the constant (8x = 40). 9 uses length + width = 40, which is only half the perimeter.

Source: OpenStax, Prealgebra 2e, §7.3 Distributive Property.

Question 83 · Algebra · Problem Solving

A club has $220. It spends $40 on a banner and wants to buy T-shirts that cost $18 each. What is the greatest number of T-shirts the club can buy without spending more than $220?

A. 9
B. 12
C. 10
D. 14

Answer: C. 10

Write 40 + 18n ≤ 220. Subtract 40: 18n ≤ 180. Divide: n ≤ 10, so the club can buy 10 shirts and spend exactly $220. 9 treats “not more than” as “less than,” which wrongly rules out spending exactly $220. 12 ignores the banner (220 ÷ 18 is about 12.2). 14 adds the banner cost instead of subtracting it.

Source: OpenStax, Elementary Algebra 2e, §2.7 Solve Linear Inequalities.

Data and Information (Questions 84–90)

Question 84 · Data and Information · Computation

What is the mean of 8, 10, 13, 17, and 27?

A. 13
B. 19
C. 75
D. 15

Answer: D. 15

The mean is the sum divided by the count: 8 + 10 + 13 + 17 + 27 = 75, and 75 ÷ 5 = 15. 13 is the median (the middle value). 19 is the range (27 − 8). 75 is the sum before dividing.

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Question 85 · Data and Information · Computation

What is the median of 4, 9, 2, 7, 12, and 6?

A. 4.5
B. about 6.7
C. 6.5
D. 10

Answer: C. 6.5

Put the values in order first: 2, 4, 6, 7, 9, 12. With six values, the median is the mean of the two middle ones: (6 + 7) ÷ 2 = 6.5. 4.5 averages the two middle values of the unsorted list (2 and 7). About 6.7 is the mean (40 ÷ 6). 10 is the range (12 − 2).

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Question 86 · Data and Information · Computation

What is the mode of this data set? 3, 5, 5, 6, 8, 8, 9

A. 6
B. 8 only
C. 5 and 8
D. There is no mode.

Answer: C. 5 and 8

The mode is the value that appears most often. Here 5 and 8 each appear twice, and every other value appears once, so the set has two modes: 5 and 8. 6 is the median. “8 only” misses the tie with 5. Both 5 and 8 tie for the greatest frequency, so “no mode” does not describe this set.

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Question 87 · Data and Information · Problem Solving

Class A's quiz scores were 70, 75, 80, 85, and 90. Class B's scores were 60, 78, 82, 84, and 96. Which statement is true?

A. Class A's median is 2 points higher than Class B's.
B. Class B's median is 2 points higher than Class A's.
C. The two classes have the same median.
D. Class B's median is 16 points higher than Class A's.

Answer: B. Class B's median is 2 points higher than Class A's.

Both lists are already in order. Class A's median is 80 and Class B's is 82, so B's is 2 points higher. The “same median” trap comes from the means: both classes average exactly 80, but the question is about medians. 16 points is the difference between the ranges (36 − 20), not the medians.

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Question 88 · Data and Information · Problem Solving

Volunteers per month. January: 14, February: 22, March: 18, April: 30. Hypothetical data; values also appear in the table.

Volunteers per month (hypothetical bar graph values)

Data and Information (Questions 84–90) table
MonthJanuaryFebruaryMarchApril
Volunteers14221830

A bar graph shows how many volunteers helped at a food bank each month; its values are shown in the table. How many more volunteers were there in the month with the most volunteers than in the month with the fewest?

A. 16
B. 8
C. 12
D. 44

Answer: A. 16

The most volunteers came in April (30) and the fewest in January (14): 30 − 14 = 16. 8 compares January with February. 12 compares April with March. 44 adds the most and the fewest instead of subtracting.

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Question 89 · Data and Information · Problem Solving

Daily museum visitors. Monday: 42, Tuesday: 47, Wednesday: 38, Thursday: 49, Friday: 45. Hypothetical data; values also appear in the table.

Daily museum visitors (hypothetical line graph values)

Data and Information (Questions 84–90) table
DayMondayTuesdayWednesdayThursdayFriday
Visitors4247384945

A line graph shows daily visitors to a small museum; its values are shown in the table. Between which two days did the number of visitors increase the most?

A. Wednesday to Thursday
B. Monday to Tuesday
C. Tuesday to Wednesday
D. Thursday to Friday

Answer: A. Wednesday to Thursday

Find each day-to-day change: Monday to Tuesday +5, Tuesday to Wednesday −9, Wednesday to Thursday +11, Thursday to Friday −4. The largest increase is +11, Wednesday to Thursday. Tuesday to Wednesday is a decrease, not an increase. Thursday has the highest count, but the question asks about the increase, not the highest day.

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Question 90 · Data and Information · Problem Solving

A clinic recorded these wait times, in minutes: 31, 33, 34, 35, 36, 38, 95. Which value best describes a typical wait?

A. The mean, about 43 minutes, because it is the only measure that uses every value.
B. The median, 35 minutes, because the one 95-minute wait pulls the mean upward.
C. The range, 64 minutes, because it shows how far apart the shortest and longest waits are.
D. The mode, because one of the wait times appears more often than the others.

Answer: B. The median, 35 minutes, because the one 95-minute wait pulls the mean upward.

Six of the seven waits fall between 31 and 38 minutes. The single 95-minute wait is an outlier that raises the mean to about 43 (302 ÷ 7), higher than every wait but one. The median, 35, sits right in the typical group. The range (95 − 31 = 64) describes spread, not a typical value. No wait time repeats, so there is no mode.

Source: OpenStax, Prealgebra 2e, §5.5 Averages and Probability.

Science practice questions

Questions 91–145. Tables marked hypothetical contain made-up data for interpretation practice; the science behind every answer is sourced in its explanation. Optional count-based pacing estimate: about 55 minutes (method and limits).

Biology (Questions 91–110)

Question 91 · Biology · Knowledge

Which cell structure assembles proteins?

A. mitochondrion
B. nucleus
C. ribosome
D. lysosome

Answer: C. ribosome

Ribosomes are the cell's protein builders; they read messenger RNA and link amino acids into proteins. The mitochondrion makes most of the cell's ATP (usable energy). The nucleus stores DNA and directs the cell, but it isn't where proteins are assembled. Lysosomes break down worn-out parts and wastes.

Source: OpenStax, Biology 2e, §4.3 Eukaryotic Cells.

Question 92 · Biology · Knowledge

Which pair of structures is found in photosynthetic plant cells but not in animal cells?

A. nucleus and cell membrane
B. mitochondria and ribosomes
C. cell wall and chloroplasts
D. cytoplasm and Golgi apparatus

Answer: C. cell wall and chloroplasts

Photosynthetic plant cells have a rigid cell wall outside the membrane and chloroplasts for photosynthesis; animal cells have neither. Every other pair lists structures that plant and animal cells share, including mitochondria. Plants need mitochondria too, to release energy from the sugar they make.

Source: OpenStax, Biology 2e, §4.3 Eukaryotic Cells.

Question 93 · Biology · Application

A student places red blood cells in a salt solution whose solute concentration is higher than that of the cells' cytoplasm. Assume water can cross the cell membrane but the dissolved solute cannot during the observation. What will most likely happen to the cells?

A. Water will move into the cells, and they may burst.
B. Salt will move into the cells until they burst.
C. There will be no net movement of water.
D. Water will move out of the cells, and they will shrink.

Answer: D. Water will move out of the cells, and they will shrink.

With the solute unable to cross the membrane, the solution is hypertonic to the cells, so water leaves by osmosis and they shrink. Water moving in until cells burst describes a hypotonic solution, where the outside has less solute. The salt choice mixes up solute movement with osmosis; this question is about water. No net movement describes an isotonic solution, where concentrations match.

Source: OpenStax, Biology for AP Courses, §5.2 Passive Transport (tonicity).

Question 94 · Biology · Knowledge

Which statement best describes simple diffusion?

A. Particles move from an area of lower concentration to an area of higher concentration using energy from ATP.
B. Only water moves, and only toward the side with less solute.
C. Particles move from an area of higher concentration to an area of lower concentration without the cell using energy.
D. The membrane surrounds a large particle and pulls it into the cell.

Answer: C. Particles move from an area of higher concentration to an area of lower concentration without the cell using energy.

Diffusion is passive: particles spread from where they are crowded to where they are less crowded, and the cell spends no energy. Moving against the gradient with ATP is active transport. The water-only choice gets osmosis backward; water moves toward the side with more solute. Wrapping around a particle to take it in is endocytosis.

Source: OpenStax, Biology for AP Courses, §5.2 Passive Transport (tonicity).

Question 95 · Biology · Knowledge

In animals, which process produces haploid gametes (egg and sperm cells) from a diploid cell?

A. mitosis
B. meiosis
C. binary fission
D. fertilization

Answer: B. meiosis

In animal gamete formation, meiosis halves the chromosome number from diploid (two sets) to haploid (one set). Mitosis makes genetically identical cells with the same chromosome number. Binary fission is how bacteria divide. Fertilization does the reverse of meiosis, joining two haploid gametes into a diploid zygote.

Source: OpenStax, Biology 2e, §11.1 The Process of Meiosis.

Question 96 · Biology · Application

The body cells of a certain species contain 24 chromosomes (2n = 24). How many chromosomes are in each of its gametes?

A. 6
B. 24
C. 48
D. 12

Answer: D. 12

Gametes are made by meiosis, which halves the chromosome number: 24 ÷ 2 = 12 (n = 12). 24 is the body-cell number, which mitosis would keep. 48 doubles it, and 6 halves it twice. When two gametes of 12 join at fertilization, the offspring is back to 24.

Source: OpenStax, Biology 2e, §11.1 The Process of Meiosis.

Question 97 · Biology · Knowledge

In double-stranded DNA, which sequence pairs base by base with ATGCCA?

A. UACGGU
B. ATGCCA
C. GCATTG
D. TACGGT

Answer: D. TACGGT

In DNA, adenine (A) pairs with thymine (T), and guanine (G) pairs with cytosine (C). Going letter by letter, ATGCCA pairs with TACGGT. UACGGU uses uracil (U), which is found in RNA, not DNA. ATGCCA just repeats the original strand. GCATTG pairs A with G and T with C, which breaks the base-pairing rules.

Source: OpenStax, Biology 2e, §14.2 DNA Structure and Sequencing.

Question 98 · Biology · Application

In pea plants, violet flowers (A) are dominant over white flowers (a). A plant with genotype Aa is crossed with a plant with genotype aa. What percentage of the offspring are expected to have white flowers?

A. 0%
B. 25%
C. 50%
D. 75%

Answer: C. 50%

A Punnett square for Aa × aa gives Aa, Aa, aa, aa. Only aa plants show the recessive white color, so 2 of 4, or 50%, are expected to be white. 25% is the answer for an Aa × Aa cross. 0% would require one parent to be AA. 75% is the share of dominant-looking offspring from Aa × Aa.

Source: OpenStax, Biology 2e, §12.2 Characteristics and Traits (Punnett squares).

Question 99 · Biology · Knowledge

What is the process in which the information in a gene's DNA is copied into messenger RNA (mRNA)?

A. transcription
B. translation
C. replication
D. mutation

Answer: A. transcription

Transcription copies a gene's DNA sequence into mRNA. Translation is the next step, when ribosomes read the mRNA to build a protein. Replication copies the entire DNA molecule before a cell divides. A mutation is a change in the DNA sequence, not a copying process.

Source: OpenStax, Biology 2e, §15.1 The Genetic Code.

Question 100 · Biology · Knowledge

What are the main products of photosynthesis?

A. carbon dioxide and water
B. oxygen and carbon dioxide
C. nitrogen and glucose
D. glucose and oxygen

Answer: D. glucose and oxygen

Photosynthesis uses light energy to turn carbon dioxide and water into glucose (a sugar) and oxygen. Carbon dioxide and water are the starting materials, not the products. Carbon dioxide is taken in, not released, by photosynthesis. Nitrogen isn't part of the reaction.

Source: OpenStax, Biology 2e, §8.1 Overview of Photosynthesis.

Question 101 · Biology · Application

Which change would most likely lower the rate of photosynthesis in a healthy green plant?

A. giving the plant air with more carbon dioxide
B. moving the plant from a sunny spot into a dark closet
C. watering the plant when its soil is dry
D. moving the plant to a sunnier window

Answer: B. moving the plant from a sunny spot into a dark closet

Photosynthesis runs on light energy, so taking away light lowers the rate. Extra carbon dioxide supplies a raw material and can increase the rate when carbon dioxide is limiting. Watering dry soil provides the other raw material, water. A sunnier window adds light.

Source: OpenStax, Biology 2e, §8.1 Overview of Photosynthesis.

Question 102 · Biology · Interpretation

Identification key

Biology (Questions 91–110) table
StepIf the animal…Then…
1ahas feathersBird
1bhas no feathersGo to step 2
2ahas hair or furMammal
2bhas no hair or furGo to step 3
3ahas moist skin without scalesAmphibian
3bhas dry skin covered with scalesReptile

Use the key to identify an animal that has no feathers, no hair or fur, and dry skin covered with scales.

A. bird
B. reptile
C. mammal
D. amphibian

Answer: B. reptile

Follow the key step by step. Step 1: no feathers, so go to 2. Step 2: no hair or fur, so go to 3. Step 3: dry, scaly skin leads to reptile. Bird requires feathers, mammal requires hair or fur, and amphibian requires moist skin without scales. The key does the sorting; the traits match how biologists describe these groups.

Source: OpenStax, Biology 2e, §29.4 Reptiles.

Question 103 · Biology · Application

Green beetles and brown beetles live on brown tree bark. Birds spot and eat green beetles more often than brown ones. Beetle color is inherited. After many generations, what is the most likely result?

A. Brown beetles make up a larger share of the population.
B. Individual green beetles turn brown during their lifetimes.
C. The share of each color stays the same.
D. The beetles stop reproducing until the birds leave.

Answer: A. Brown beetles make up a larger share of the population.

This is natural selection. Brown beetles survive and reproduce more often, and they pass the brown trait on, so brown becomes more common over generations. Individual beetles don't change color because they need to; populations change because survival differs. With other influences unchanged, this survival advantage favors a larger brown share over generations; it does not guarantee a particular proportion. Nothing suggests the beetles stop reproducing.

Source: OpenStax, Biology 2e, §18.1 Understanding Evolution.

Question 104 · Biology · Knowledge

Organisms that make their own food using energy from sunlight, such as plants, are called

A. consumers
B. decomposers
C. parasites
D. producers

Answer: D. producers

Photosynthetic producers (autotrophs) capture energy from sunlight and store it in food they make themselves, forming the base of food chains. Consumers get energy by eating other organisms. Decomposers break down dead material. Parasites feed on a living host.

Source: OpenStax, Biology 2e, §46.2 Energy Flow through Ecosystems.

Question 105 · Biology · Interpretation

Hypothetical population counts

Biology (Questions 91–110) table
Year12345
Rabbits400600900500300
Foxes2025405530

The table shows hypothetical population counts for rabbits and the foxes that prey on them. Which statement is best supported by the data?

A. Fox numbers peaked the year after rabbit numbers peaked.
B. Both populations peaked in the same year.
C. Rabbit numbers rose every year.
D. Fox numbers were larger than rabbit numbers every year.

Answer: A. Fox numbers peaked the year after rabbit numbers peaked.

Rabbits peak in Year 3 (900) and foxes peak in Year 4 (55), one year later. A lag like this is common in predator–prey data: more prey supports more predators, and more predators then cut the prey population. The same-year choice misreads the table. Rabbit numbers fall in Years 4 and 5. Foxes are fewer than rabbits in every year in this table.

Source: OpenStax, Biology 2e, §45.6 Community Ecology.

Question 106 · Biology · Knowledge

Which feature describes bacterial cells?

A. They have no nucleus.
B. They have no DNA.
C. They have no cell membrane.
D. They have no ribosomes.

Answer: A. They have no nucleus.

Bacteria are prokaryotes: their DNA sits in the cytoplasm instead of inside a membrane-bound nucleus. They still have DNA, a cell membrane, and ribosomes.

Source: OpenStax, Biology 2e, §4.2 Prokaryotic Cells.

Question 107 · Biology · Application

Why don't antibiotics cure illnesses caused by viruses, such as the common cold?

A. Antibiotics work only after an illness has lasted 10 days.
B. Antibiotics act against bacteria, and viruses are not bacteria.
C. Viruses are too large for antibiotics to reach.
D. Antibiotics destroy the body's white blood cells.

Answer: B. Antibiotics act against bacteria, and viruses are not bacteria.

The CDC's guidance is that antibiotics do not work on infections caused by viruses, such as colds and flu. Antibiotics target bacteria; viruses are a different kind of germ. There's no 10-day rule. Viruses are much smaller than bacteria, not larger. Antibiotics are not designed to destroy white blood cells.

Source: CDC, Healthy Habits: Antibiotic Do’s and Don’ts.

Question 108 · Biology · Knowledge

In an experiment comparing a new treatment with no treatment, what is the purpose of the untreated control group?

A. It receives the largest amount of the treatment so that any effect is easy to see.
B. It is chosen so that the results come out the way the researcher predicted.
C. It does not receive the treatment being tested, so the results can be compared with the group that does.
D. It is the only group whose results are measured at the end of the experiment.

Answer: C. It does not receive the treatment being tested, so the results can be compared with the group that does.

A control group is the comparison point. It's handled the same way as the experimental group except for the factor being tested, helping researchers assess that factor while reducing alternative explanations. Giving it the largest dose makes it an experimental group. Choosing groups to get a predicted result is bias. Both groups are measured; that's the point of comparing them.

Source: OpenStax, Biology 2e, §1.1 The Science of Biology.

Question 109 · Biology · Application

A student wants to test whether a fertilizer affects how tall bean plants grow. Which design is the fairest test?

A. Two groups of bean plants get the same light, water, soil, and pot size, and only one group gets the fertilizer.
B. Fertilized plants are placed by a window, and unfertilized plants are placed in a closet.
C. Both groups get fertilizer, and one group also gets extra water.
D. The fertilized group gets fertilizer and more water, and the other group gets neither.

Answer: A. Two groups of bean plants get the same light, water, soil, and pot size, and only one group gets the fertilizer.

A fair test changes one variable, the fertilizer, and keeps everything else the same, to reduce alternative explanations for a difference in height. The window-and-closet design also changes light. Giving both groups fertilizer means nothing tests fertilizer. Changing fertilizer and water together makes it impossible to tell which one mattered.

Source: OpenStax, Biology 2e, §1.1 The Science of Biology.

Question 110 · Biology · Interpretation

Hypothetical enzyme activity

Biology (Questions 91–110) table
Temperature (°C)102030405060
Activity (units)12254155182

The table shows hypothetical results from an experiment measuring an enzyme's activity at different temperatures. Which conclusion is best supported?

A. Activity rose steadily the whole time as the temperature went up.
B. The enzyme worked best at 60°C, the highest temperature tested.
C. Temperature had no clear effect on how active the enzyme was.
D. Of the temperatures tested, activity was highest at 40°C and dropped sharply above it.

Answer: D. Of the temperatures tested, activity was highest at 40°C and dropped sharply above it.

Activity climbs from 12 to 55 units up to 40°C, then falls to 18 and 2. That fits how enzymes behave: warmth speeds reactions up to a point, but too much heat changes the enzyme's shape and it stops working well. Activity doesn't rise steadily; it drops after 40°C. At 60°C activity is lowest, not highest. The values change a lot, so temperature clearly matters. Note the careful wording: “of the temperatures tested.”

Source: OpenStax, Biology 2e, §6.5 Enzymes.

Human Anatomy (Questions 111–121)

Question 111 · Human Anatomy · Interpretation

Blood-flow diagram

Right ventricle → pulmonary arteries → lungs → pulmonary veins → [ ? ] → left ventricle → aorta

The diagram shows part of the path blood takes through the heart and lungs. Which structure belongs in the blank?

A. left atrium
B. right atrium
C. superior vena cava
D. pulmonary trunk

Answer: A. left atrium

Pulmonary veins carry oxygen-rich blood from the lungs back to the heart, and they empty into the left atrium. From there, blood passes into the left ventricle, which pumps it out through the aorta. The right atrium receives oxygen-poor blood from the body. The superior vena cava is one of the veins that delivers that blood. The pulmonary trunk carries blood away from the right ventricle toward the lungs.

Source: OpenStax, Anatomy and Physiology 2e, §19.1 Heart Anatomy.

Question 112 · Human Anatomy · Knowledge

Where are the adrenal glands located?

A. at the base of the brain
B. on top of the kidneys
C. in the neck, below the larynx
D. behind the stomach

Answer: B. on top of the kidneys

The adrenal glands sit atop the kidneys, attached by a fibrous capsule. The gland at the base of the brain is the pituitary. The gland in the neck below the larynx is the thyroid. The pancreas lies behind the stomach.

Source: OpenStax, Anatomy and Physiology 2e, §17.6 The Adrenal Glands.

Question 113 · Human Anatomy · Knowledge

What are the tiny, finger-like projections that line the small intestine called?

A. alveoli
B. villi
C. nephrons
D. rugae

Answer: B. villi

Villi line the small intestine and greatly increase its surface area for absorbing nutrients. Alveoli are air sacs in the lungs. Nephrons are the filtering units of the kidneys. Rugae are folds in the stomach lining.

Source: OpenStax, Anatomy and Physiology 2e, §23.5 The Small and Large Intestines.

Question 114 · Human Anatomy · Knowledge

Which layer of the skin is the outermost?

A. dermis
B. hypodermis
C. periosteum
D. epidermis

Answer: D. epidermis

The epidermis is the outer layer of the skin. The dermis lies beneath it and holds blood vessels, nerves, and glands. The hypodermis (subcutaneous layer) is deeper still. The periosteum isn't part of the skin; it covers bones.

Source: OpenStax, Anatomy and Physiology 2e, §5.1 Layers of the Skin.

Question 115 · Human Anatomy · Application

During a sore throat, a person notices small, tender swellings along the side of the neck. Which lymph-filtering structures are these most likely to be?

A. lymph nodes
B. thyroid lobes
C. vocal cords
D. salivary glands

Answer: A. lymph nodes

Lymph nodes sit along lymphatic vessels, including many in the neck, and filter lymph as immune cells respond to infection. The question's clue, structures that filter lymph, points directly to them. The thyroid is a single gland at the front of the neck. The vocal cords are inside the larynx. Salivary glands make saliva; they don't filter lymph.

Source: OpenStax, Anatomy and Physiology 2e, §21.1 Anatomy of the Lymphatic and Immune Systems.

Question 116 · Human Anatomy · Interpretation

Arm diagram (from the trunk outward)

Trunk → shoulder → upper arm → elbow → forearm → wrist → fingertips

The diagram lists points along the arm, starting from where the arm attaches to the trunk. Which point is distal to the elbow?

A. shoulder
B. wrist
C. upper arm
D. collarbone

Answer: B. wrist

Distal means farther from where a limb attaches to the trunk. On the diagram, the wrist lies beyond the elbow, so it is distal to it. The shoulder and upper arm lie closer to the trunk, so they are proximal to the elbow. The collarbone is part of the shoulder girdle, closer to the trunk still.

Source: OpenStax, Anatomy and Physiology 2e, §1.6 Anatomical Terminology.

Question 117 · Human Anatomy · Knowledge

The central nervous system consists of the

A. brain and cranial nerves
B. brain and spinal cord
C. spinal cord and spinal nerves
D. nerves in the arms and legs

Answer: B. brain and spinal cord

The central nervous system (CNS) is the brain and spinal cord. Nerves that branch out from them, including cranial and spinal nerves, make up the peripheral nervous system. Each wrong choice mixes in peripheral nerves or leaves out part of the CNS.

Source: OpenStax, Anatomy and Physiology 2e, §12.1 Basic Structure and Function of the Nervous System.

Question 118 · Human Anatomy · Knowledge

Where does fertilization of an egg usually take place?

A. in the lining of the uterus
B. inside the ovary
C. in the uterine (fallopian) tube
D. in the cervix

Answer: C. in the uterine (fallopian) tube

Fertilization usually happens in the outer part of the uterine tube, after an oocyte (egg) is released from the ovary and enters the tube. The fertilized egg then travels to the uterus and implants in its lining, which is why the uterus is a tempting trap. The ovary releases the egg but isn't where it's usually fertilized. The cervix is the narrow lower part of the uterus.

Source: OpenStax, Anatomy and Physiology 2e, §27.2 Anatomy and Physiology of the Ovarian Reproductive System.

Question 119 · Human Anatomy · Application

Gas exchange works best across structures with very thin walls, a huge total surface area, and a dense network of capillaries. Which respiratory structures best fit this description?

A. alveoli
B. trachea
C. bronchi
D. larynx

Answer: A. alveoli

Alveoli are tiny air sacs with walls only a cell or so thick, wrapped in capillaries. Together they create an enormous surface for oxygen and carbon dioxide to cross. The trachea and bronchi are airways reinforced with cartilage, built to conduct air rather than exchange gases. The larynx houses the vocal cords.

Source: OpenStax, Anatomy and Physiology 2e, §22.1 Organs and Structures of the Respiratory System.

Question 120 · Human Anatomy · Interpretation

Urine-flow diagram

Kidney → X → urinary bladder → Y → outside the body

The diagram shows the path urine takes out of the body. Which structure is labeled X?

A. urethra
B. renal vein
C. ureter
D. nephron

Answer: C. ureter

Urine made in the kidney travels down a ureter to the urinary bladder, so X is the ureter. The urethra (Y) carries urine from the bladder out of the body; the two names are easy to mix up. The renal vein carries blood, not urine. Nephrons are the tiny filtering units inside the kidney.

Source: OpenStax, Anatomy and Physiology 2e, §25.2 Gross Anatomy of Urine Transport.

Question 121 · Human Anatomy · Application

After an inner-ear problem, a person feels dizzy and has trouble keeping balance, but their hearing is unchanged. Which part of the inner ear is most involved in the balance problem?

A. the cochlea
B. the eardrum
C. the tiny bones of the middle ear
D. the semicircular canals and vestibule

Answer: D. the semicircular canals and vestibule

The semicircular canals and vestibule detect head movement and position, so they handle balance. The cochlea handles hearing, and hearing is unchanged. The eardrum and middle-ear bones pass sound vibrations along; they aren't part of the inner ear's balance system.

Source: OpenStax, Anatomy and Physiology 2e, §14.1 Sensory Perception.

Human Physiology (Questions 122–132)

Question 122 · Human Physiology · Application

Cardiac output = heart rate × stroke volume. A person's heart rate rises from 70 to 100 beats per minute while stroke volume stays at 70 milliliters per beat. What happens to cardiac output?

A. It stays the same.
B. It rises from 4.9 to 7.0 liters per minute.
C. It rises from 70 to 100 milliliters per minute.
D. It falls, because the heart has less time to fill.

Answer: B. It rises from 4.9 to 7.0 liters per minute.

Use the formula: 70 × 70 = 4,900 mL per minute (4.9 L), and 100 × 70 = 7,000 mL per minute (7.0 L). A higher heart rate with the same stroke volume means more blood pumped each minute. It can't stay the same when one factor rises and the other holds steady. The milliliters choice confuses heart rate with output. The “less time to fill” choice contradicts the question, which says stroke volume stays at 70 mL.

Source: OpenStax, Anatomy and Physiology 2e, §19.4 Cardiac Physiology.

Question 123 · Human Physiology · Application

After a meal, blood glucose rises. The pancreas releases insulin, which helps cells take up glucose, and blood glucose falls back toward its normal level. This is an example of

A. positive feedback
B. a reflex arc
C. an allergic response
D. negative feedback

Answer: D. negative feedback

In negative feedback, a change triggers a response that pushes the value back toward normal. Rising glucose leads to insulin, which lowers glucose. Positive feedback would push the change even further in the same direction. A reflex arc is a nerve pathway, and an allergic response is an immune reaction; neither describes this hormone loop.

Source: OpenStax, Anatomy and Physiology 2e, §1.5 Homeostasis; OpenStax, Anatomy and Physiology 2e, §17.9 The Endocrine Pancreas.

Question 124 · Human Physiology · Knowledge

Bile is made by the liver and stored in the gallbladder. How does bile mainly help digestion?

A. It breaks proteins down into amino acids.
B. It breaks large fat globules into smaller droplets.
C. It absorbs water from undigested food.
D. It releases insulin into the blood.

Answer: B. It breaks large fat globules into smaller droplets.

Bile emulsifies fats, breaking big fat globules into tiny droplets that digestive enzymes can work on more easily. Enzymes, not bile, break proteins into amino acids. Most water from undigested food is absorbed in the intestines. Insulin comes from the pancreas.

Source: OpenStax, Anatomy and Physiology 2e, §23.6 Accessory Organs in Digestion: The Liver, Pancreas, and Gallbladder.

Question 125 · Human Physiology · Application

On a hot day, which response helps the skin release excess body heat?

A. Blood vessels in the dermis narrow to keep heat in the body's core.
B. Tiny muscles raise the hairs on the skin, causing goose bumps.
C. Skeletal muscles begin to shiver.
D. Sweat glands release sweat, and blood vessels in the dermis widen.

Answer: D. Sweat glands release sweat, and blood vessels in the dermis widen.

Sweat cools the skin as it evaporates, and wider dermal blood vessels bring more warm blood near the surface, where heat can escape. Narrowing those vessels conserves heat, which is the cold-weather response. Goose bumps and shivering are also responses to cold; shivering actually makes heat.

Source: OpenStax, Anatomy and Physiology 2e, §5.3 Functions of the Integumentary System.

Question 126 · Human Physiology · Knowledge

Which cells produce antibodies?

A. helper T cells
B. B cells
C. red blood cells
D. platelets

Answer: B. B cells

Antibodies are proteins made by B cells (B lymphocytes); activated B cells develop into plasma cells that release large amounts of antibody. Helper T cells coordinate the immune response but don't make antibodies. Red blood cells carry oxygen, and platelets help blood clot.

Source: OpenStax, Anatomy and Physiology 2e, §21.4 The Adaptive Immune Response: B-lymphocytes and Antibodies.

Question 127 · Human Physiology · Knowledge

In adults, most blood cells are produced in the

A. yellow bone marrow
B. cartilage
C. red bone marrow
D. periosteum

Answer: C. red bone marrow

Red bone marrow is where blood cells are made. Yellow bone marrow mainly stores fat. Cartilage is flexible connective tissue at joints and in other places. The periosteum is the membrane covering the outside of bones.

Source: OpenStax, Anatomy and Physiology 2e, §6.1 The Functions of the Skeletal System.

Question 128 · Human Physiology · Interpretation

Reflex diagram

Pain receptor (nociceptor) in skin → Label 1 → spinal cord → Label 2 → arm muscle contracts

The diagram shows a simple reflex that pulls a hand away from a hot surface. Which label marks the motor neuron?

A. Label 2
B. Label 1
C. the receptor
D. the spinal cord

Answer: A. Label 2

Follow the signal. The receptor in the skin detects painful heat, and Label 1 is the sensory neuron that carries the message to the spinal cord. The spinal cord relays it, and Label 2 is the motor neuron that carries the command out to the muscle. The receptor and spinal cord are real parts of the reflex, but neither is the motor neuron.

Source: OpenStax, Anatomy and Physiology 2e, §14.3 Motor Responses: withdrawal reflex.

Question 129 · Human Physiology · Knowledge

During a typical menstrual cycle, which organs are the main source of estrogen and progesterone?

A. testes
B. thyroid gland
C. pituitary gland
D. ovaries

Answer: D. ovaries

The ovaries produce estrogen and progesterone. The testes primarily produce testosterone, not the main supply of these ovarian-cycle hormones. The thyroid gland makes hormones that regulate metabolism. The pituitary releases hormones (such as FSH and LH) that signal the ovaries, but it doesn't make estrogen and progesterone itself.

Source: OpenStax, Anatomy and Physiology 2e, §27.2 Anatomy and Physiology of the Ovarian Reproductive System.

Question 130 · Human Physiology · Interpretation

Hypothetical breathing data

Human Physiology (Questions 122–132) table
Blood CO₂ levelNormalSlightly raisedRaisedHigh
Breaths per minute12162228

The table shows hypothetical measurements of breathing rate at different blood carbon dioxide (CO₂) levels. Which statement is best supported?

A. Breathing rate decreased as blood CO₂ increased.
B. Breathing rate stayed about the same at every CO₂ level.
C. Breathing rate increased as blood CO₂ increased.
D. The table shows that faster breathing raises blood CO₂.

Answer: C. Breathing rate increased as blood CO₂ increased.

Reading left to right, CO₂ goes up and breathing rate climbs from 12 to 28 breaths per minute. That matches physiology: rising CO₂ stimulates chemoreceptors, which increase breathing rate and depth to help remove the extra CO₂. The first two wrong choices misread the table. The last choice makes a causal claim that the table cannot establish. A higher breathing rate alone does not tell you how much fresh air reaches the alveoli; breathing depth matters too.

Source: OpenStax, Anatomy and Physiology 2e, §22.3 The Process of Breathing.

Question 131 · Human Physiology · Application

When a person is dehydrated, the body releases more antidiuretic hormone (ADH). What is the most likely effect?

A. The kidneys reabsorb less water, so urine becomes more dilute.
B. The bladder stops filling until the person drinks water.
C. The kidneys reabsorb more water, so urine becomes more concentrated.
D. The kidneys stop filtering blood.

Answer: C. The kidneys reabsorb more water, so urine becomes more concentrated.

ADH increases how much water the kidneys reabsorb from their collecting tubules back into the blood. Less water leaves in urine, so urine is more concentrated. That helps conserve water during dehydration. Less water reabsorbed is the effect of low ADH. Urine production slows but doesn't stop, and filtering continues.

Source: OpenStax, Anatomy and Physiology 2e, §26.2 Water Balance: ADH.

Question 132 · Human Physiology · Interpretation

Hypothetical pupil measurements

Human Physiology (Questions 122–132) table
LightingDim roomNormal roomBright sunlight
Pupil diameter (mm)742

The table shows hypothetical pupil diameters measured in different lighting. Which statement is best supported?

A. Pupil diameter increased as the light became brighter.
B. Pupil diameter decreased as the light became brighter.
C. Pupil diameter stayed the same in all lighting.
D. The pupil was largest in bright sunlight.

Answer: B. Pupil diameter decreased as the light became brighter.

The pupil shrinks from 7 mm in a dim room to 2 mm in bright sunlight. That's the pupillary light reflex: in bright light the pupil constricts to limit the light reaching the retina, and in dim light it dilates. The other choices contradict the table.

Source: OpenStax, Anatomy and Physiology 2e, §15.2 Autonomic Reflexes and Homeostasis.

Chemistry (Questions 133–137)

Question 133 · Chemistry · Knowledge

Carbon-12 and carbon-14 are isotopes of carbon. How do their atoms differ?

A. They have different numbers of protons.
B. They have different numbers of neutrons.
C. Their neutral atoms have different numbers of electrons.
D. They have different atomic numbers.

Answer: B. They have different numbers of neutrons.

Isotopes of an element have the same number of protons, which is what makes both atoms carbon, but different numbers of neutrons. That's why their mass numbers (12 and 14) differ. A different number of protons would make them different elements. Neutral atoms of the same element have the same number of electrons, because electrons match protons. The atomic number is the proton count, so it's the same for both.

Source: OpenStax, Chemistry 2e, §2.3 Atomic Structure and Symbolism.

Question 134 · Chemistry · Knowledge

How does the bond form when sodium and chlorine combine to make sodium chloride?

A. Sodium transfers an electron to chlorine, forming oppositely charged ions that attract each other.
B. Sodium and chlorine share a pair of electrons equally between their nuclei.
C. Chlorine transfers a proton to sodium, and the two nuclei attract each other.
D. The atoms share electrons unequally, forming a polar covalent bond.

Answer: A. Sodium transfers an electron to chlorine, forming oppositely charged ions that attract each other.

Sodium chloride has an ionic bond. The sodium atom gives up an electron to become Na⁺, chlorine gains it to become Cl⁻, and the opposite charges attract. Sharing electrons, whether equally or unequally, describes covalent bonds, not table salt. Protons stay in the nucleus; bonding involves electrons.

Source: OpenStax, Chemistry 2e, §7.1 Ionic Bonding.

Question 135 · Chemistry · Application

A sealed, rigid container of gas is heated. What happens to the pressure inside, and why?

A. It increases, because the gas particles move faster and hit the walls more often and with more force.
B. It decreases, because the heated gas particles spread farther apart from each other.
C. It stays the same, because the number of gas particles inside does not change.
D. It increases, because each gas particle grows larger as it absorbs heat.

Answer: A. It increases, because the gas particles move faster and hit the walls more often and with more force.

Heat raises the particles' average kinetic energy, so they move faster. In a rigid container the volume can't change, so faster particles collide with the walls more often and harder, and pressure rises. The particles can't spread farther apart in a rigid container. The same number of particles still pushes harder when they move faster. The particles themselves don't grow.

Source: OpenStax, Chemistry 2e, §9.5 The Kinetic-Molecular Theory.

Question 136 · Chemistry · Knowledge

Mayonnaise contains tiny droplets of oil spread throughout a water-based liquid, with egg yolk keeping the droplets from separating. This mixture is best classified as

A. a solution
B. a pure compound
C. an emulsion
D. a tincture

Answer: C. an emulsion

An emulsion is a mixture of two liquids that normally don't mix, with one spread through the other as tiny droplets, often held in place by an emulsifier such as egg yolk. In a solution the dissolved substance mixes evenly at the level of molecules or ions, which oil in water doesn't do. A pure compound isn't a mixture at all. A tincture is a solution made with alcohol as the solvent.

Source: OpenStax, Chemistry 2e, §11.5 Colloids; Merriam-Webster, “tincture”.

Question 137 · Chemistry · Interpretation

Four solutions

Chemistry (Questions 133–137) table
SolutionWXYZ
pH25711

Note: Assume dilute aqueous solutions at 25°C. Each decrease of 1 pH unit means the hydronium-ion (H₃O⁺) concentration is 10 times greater.

Use the table and its note. Which solution is the most acidic, and how does its hydronium-ion concentration compare with solution X's?

A. W; about 3 times greater
B. Z; about 1,000 times greater
C. Y; about 100 times greater
D. W; about 1,000 times greater

Answer: D. W; about 1,000 times greater

Lower pH means more acidic, so W (pH 2) is the most acidic. It is 3 pH units below X (pH 5), and each unit is a factor of 10, so 10 × 10 × 10 = 1,000. “3 times” treats the pH scale as if it were linear. Z has the highest pH, so it's basic, not acidic. Y (pH 7) is neutral and sits 2 units above X, so its hydronium-ion concentration is 100 times lower than X's, not higher.

Source: OpenStax, Chemistry 2e, §14.2 pH and pOH.

Health (Questions 138–145)

Question 138 · Health · Knowledge

How does the World Health Organization's constitution define health?

A. the absence of any disease, injury, or physical disability
B. having a normal body weight and normal blood pressure readings
C. complete physical, mental, and social well-being, not just the absence of disease
D. being able to work and attend school without taking sick days

Answer: C. complete physical, mental, and social well-being, not just the absence of disease

The WHO constitution describes health as complete physical, mental, and social well-being and not merely the absence of disease or infirmity. “The absence of disease” is exactly what the definition says health is more than. Body weight, blood pressure, and missed workdays are narrow measures, not a definition of health.

Source: World Health Organization, Constitution.

Question 139 · Health · Application

Before eating, Jordan wets his hands, adds soap, rubs them together for about 5 seconds, rinses, and dries them with a clean towel. Which change would best match CDC's handwashing steps?

A. Use very hot water so the soap can be skipped.
B. Skip the towel, because hands must air-dry.
C. Scrub with soap for at least 20 seconds before rinsing.
D. Rinse for 20 seconds instead of scrubbing.

Answer: C. Scrub with soap for at least 20 seconds before rinsing.

CDC's steps are wet, lather, scrub for at least 20 seconds, rinse, and dry. Jordan's only gap is the scrubbing time. CDC says warm or cold water both work, and it never says soap can be skipped. Drying with a clean towel or air-drying are both fine. The 20 seconds apply to scrubbing with soap, not rinsing.

Source: CDC, About Handwashing: five steps.

Question 140 · Health · Knowledge

According to the CDC, how much sleep do adults ages 18 to 60 need each night?

A. 7 or more hours
B. 4 to 5 hours
C. 5 to 6 hours
D. 12 or more hours

Answer: A. 7 or more hours

CDC lists 7 or more hours per night for adults ages 18 to 60. Four to six hours falls short of that. Twelve or more hours is in the range listed for young children, including naps.

Source: CDC, About Sleep: hours by age.

Question 141 · Health · Application

A parent who smokes wants to protect a young child from secondhand smoke at home. Based on CDC guidance, which step is most effective?

A. Keep the home and car completely smoke-free.
B. Smoke only in a separate room with the door closed.
C. Open a window or run a fan while smoking indoors.
D. Run an air purifier in the child's bedroom.

Answer: A. Keep the home and car completely smoke-free.

CDC says there is no safe level of secondhand smoke exposure and that only 100% smoke-free indoor air fully protects people. Smoke from another room still spreads through the home. CDC materials say opening windows, using fans, and running air purifiers don't remove secondhand smoke's harmful chemicals.

Source: CDC, Preventing Exposure to Secondhand Smoke in the Home.

Question 142 · Health · Application

After a stroke, a person receives rehabilitation to improve walking and reduce lasting disability. In the primary, secondary, and tertiary prevention framework, this is an example of

A. primary prevention
B. secondary prevention
C. tertiary prevention
D. a health screening

Answer: C. tertiary prevention

Tertiary prevention limits disability and other consequences after disease is established, such as rehabilitation to improve walking after a stroke. Primary prevention reduces risk before disease starts. Secondary prevention detects and treats disease early; screening is one of its tools. This example is about reducing established disability, not screening for an undetected disease.

Source: CDC MMWR, A Framework for Assessing the Effectiveness of Disease and Injury Prevention (1992): tertiary prevention; WHO, Rehabilitation: stroke examples and reducing disability (April 22, 2024).

Question 143 · Health · Knowledge

What is the main purpose of a health screening test?

A. to treat a disease after a doctor has already diagnosed it
B. to find a disease or risk early in people who do not yet have symptoms
C. to prevent infection by giving people a vaccine
D. to help a person regain strength and recover after an illness

Answer: B. to find a disease or risk early in people who do not yet have symptoms

Screening looks for disease in people without symptoms, when treatment can work better. That's secondary prevention. Treating a diagnosed disease isn't screening. Vaccination is primary prevention. Rehabilitation aimed at reducing established disability is tertiary prevention.

Source: CDC MMWR, A Framework for Assessing the Effectiveness of Disease and Injury Prevention (1992): prevention levels.

Question 144 · Health · Interpretation

Hypothetical data

Health (Questions 138–145) table
TownABCD
Vaccination coverage95%85%70%60%
Cases per 10,000 residents293158

The table shows hypothetical vaccination coverage and disease case rates in four towns. Which statement is best supported by the data?

A. Vaccination coverage above 60% prevents every case of the disease.
B. Town D, with the lowest coverage, reported the lowest case rate.
C. The data show that higher vaccination coverage causes higher case rates.
D. In these data, towns with higher vaccination coverage reported lower case rates.

Answer: D. In these data, towns with higher vaccination coverage reported lower case rates.

As coverage drops from 95% to 60%, the reported case rate rises from 2 to 58 per 10,000 residents. That is an association in these hypothetical data, not proof of causation. Town A has coverage above 60% (95%) and still reports 2 cases per 10,000 residents, so the “prevents every case” choice is false. Town D has the highest case rate, not the lowest. The “causes higher case rates” choice both reverses the observed direction and makes an unsupported causal claim. The table does not give the towns’ population sizes, so it cannot establish their total numbers of cases.

Source: OpenStax, Biology 2e, §1.1 The Science of Biology: evidence and testing hypotheses.

Question 145 · Health · Interpretation

Food thermometer readings

Health (Questions 138–145) table
DishThermometer readingSafe minimum (FoodSafety.gov)
Roast chicken158°F165°F
Hamburger (ground beef)162°F160°F
Baked salmon146°F145°F
Pork chop (rested 3 minutes)147°F145°F, plus a 3-minute rest

Use the safe minimum internal temperatures in the table. Which dish needs more cooking?

A. roast chicken
B. hamburger (ground beef)
C. baked salmon
D. pork chop

Answer: A. roast chicken

Compare each reading with its minimum. Roast chicken reads 158°F, but poultry needs 165°F, so it needs more cooking. The hamburger (162°F) is above its 160°F minimum. The salmon (146°F) is above its 145°F minimum. The pork chop (147°F) is above 145°F, and it has rested the required 3 minutes.

Source: FoodSafety.gov, Safe Minimum Internal Temperature Chart.

Score your practice test

Give yourself one point for each correct answer and count blanks as wrong. That mirrors the real NEX, where unanswered questions count as incorrect and there's no penalty for guessing (NLN NEX Technical Brief, p. 2). So on test day, never leave a question blank.

Record your first answer before opening its explanation. Count a question as unanswered if you viewed the answer first. For the full set, percent correct = 100 × correct ÷ 145; for a subject, divide by 50 (Verbal), 40 (Math), or 55 (Science). Round percentages to one decimal place. Do not average the three subject percentages: their denominators differ.

Score your practice test table
ResultYour count
Correct___
Incorrect attempts___
Unanswered or answer viewed first___
Total145

Answer key

Verbal (Questions 1–50)

Verbal (Questions 1–50) table
QAnswerQAnswerQAnswerQAnswerQAnswer
1D2D3B4B5C
6B7A8C9D10D
11B12D13C14D15B
16C17A18A19D20D
21B22A23A24D25A
26B27B28C29C30D
31A32C33A34B35B
36A37B38D39C40A
41B42C43A44D45C
46C47B48C49D50A

Math (Questions 51–90)

Math (Questions 51–90) table
QAnswerQAnswerQAnswerQAnswerQAnswer
51B52C53B54C55C
56D57A58C59D60A
61D62C63B64B65D
66D67B68D69B70B
71A72A73C74D75D
76A77A78B79D80A
81C82A83C84D85C
86C87B88A89A90B

Science (Questions 91–145)

Science (Questions 91–145) table
QAnswerQAnswerQAnswerQAnswerQAnswer
91C92C93D94C95B
96D97D98C99A100D
101B102B103A104D105A
106A107B108C109A110D
111A112B113B114D115A
116B117B118C119A120C
121D122B123D124B125D
126B127C128A129D130C
131C132B133B134A135A
136C137D138C139C140A
141A142C143B144D145A

Your results by content area

These are the content areas NLN uses for each test, with the same number of questions per area as the scored NEX (NLN Technical Brief, pp. 3–6).

Your results by content area table
TestContent areaQuestionsNumber of questionsYour number correct
VerbalWord Knowledge1–2525___ of 25
VerbalReading Comprehension26–5025___ of 25
MathNumbers and Operations51–6212___ of 12
MathMeasurement63–7614___ of 14
MathAlgebra77–837___ of 7
MathData and Information84–907___ of 7
ScienceBiology91–11020___ of 20
ScienceHuman Anatomy111–12111___ of 11
ScienceHuman Physiology122–13211___ of 11
ScienceChemistry133–1375___ of 5
ScienceHealth138–1458___ of 8
AllTotal1–145145___ of 145

A few areas are small: Chemistry has 5 questions, Algebra and Data and Information have 7 each, and Health has 8. One or two answers can swing those results a lot, so read them as signals, not measurements.

Your results by skill

NLN's score report also sorts results by skill, which NLN calls dimensions. We labeled every question with the same dimension names; these are our editorial classifications, not NLN-validated ratings of the items. If most of your misses are Knowledge questions, start with more content review. If they cluster in Application, Interpretation, or Problem Solving, practice using what you know on new situations and data.

Your results by skill table
TestSkill (NLN dimension)QuestionsNumber of questions
VerbalWord Analysis1–1515
VerbalVocabulary Development16–2510
VerbalReading for Information26–27, 31–32, 36–37, 41–42, 46–4710
VerbalApplication28–29, 33–34, 38–39, 43–44, 48–4910
VerbalInference30, 35, 40, 45, 505
MathComputation51–54, 63–67, 77–79, 84–8615
MathProblem Solving55–62, 68–76, 80–83, 87–9025
ScienceKnowledge91–92, 94–95, 97, 99–100, 104, 106, 108, 112–114, 117–118, 124, 126–127, 129, 133–134, 136, 138, 140, 14325
ScienceApplication93, 96, 98, 101, 103, 107, 109, 115, 119, 121–123, 125, 131, 135, 139, 141–14218
ScienceInterpretation102, 105, 110–111, 116, 120, 128, 130, 132, 137, 144–14512

NLN's report also shows a Logic and Reasoning category that combines certain skills: Word Analysis and Inference in Verbal, Problem Solving in Math, and Application and Interpretation in Science (NLN NEX Technical Brief, pp. 3–6 and 13). In this set, that's 20 Verbal, 25 Math, and 30 Science questions, the same counts as the scored NEX.

What your score means, and what it doesn't

Your percent correct describes how you did on these 145 questions. It isn't an NLN percentile, a composite score, or a prediction of your NEX result. NLN tries out its questions on real applicants and compares scores against large groups of RN and LPN/VN applicants; our questions haven't been through that process, so there's no fair way to convert this score into a NEX score.

NLN also doesn't set a passing score. Each nursing program decides what it requires (NLN Student Resources FAQ).

How to review what you missed

  1. Use the two tables above to sort your misses by content area and skill. Start with the area where you missed the largest share.
  2. Read the full explanation for each miss, including why your choice was wrong. Many misses come from a specific slip: a flipped ratio, a skipped step, a synonym trap. Naming the slip helps you catch it next time.
  3. Cover the explanation and solve the question again on paper. You want your reasoning to match the explanation, not just your letter.
  4. For any area where you missed several, work through the free review sources below, then retry those questions.

How this practice test compares with the real NEX

The National League for Nursing’s Nursing Entrance Exam (NEX) is an admissions assessment for applicants to prelicensure RN and LPN/VN programs, not a nursing license (NLN Technical Brief, p. 2). This page is for that nursing-admissions task.

How this practice test compares with the real NEX table
Real NEXThis practice test
Questions163 shown: 145 scored plus 18 unscored tryout questions145, all counted
Verbal58 shown, 50 scored: Word Knowledge 25, Reading Comprehension 2550, same split
Math45 shown, 40 scored: Numbers and Operations 12, Measurement 14, Algebra 7, Data and Information 740, same split
Science60 shown, 55 scored: Biology 20, Human Anatomy 11, Human Physiology 11, Chemistry 5, Health 855, same split
Reading passages5 scored passages plus 1 tryout passage, written at a ninth-grade level or higher5 original passages
FormatFour-option multiple choice; no guessing penalty; unanswered questions count as incorrectSame format
Time60 minutes for each subject, all in one sittingUntimed, or optional arithmetic pacing estimates of 52, 53, and 55 minutes
CalculatorBuilt into the testing platformUse a basic four-function calculator
ScoresPercentile ranks and a composite score, compared with RN and LPN/VN applicantsYour raw count and percent correct on these practice items

Sources: NLN NEX Technical Brief, pp. 2–6, 11, and 13–15; NLN NEX Technical Manual, §2.3 and §4.2.

Where the pacing numbers come from

On the real test, each 60-minute clock also covers that subject's unscored tryout questions. We scaled the clock to our shorter sections: 60 minutes × 50/58 ≈ 52 minutes for Verbal, 60 × 40/45 ≈ 53 minutes for Math, and 60 × 55/60 = 55 minutes for Science. These are arithmetic pacing estimates, not NLN timings or evidence that our items take the same amount of time as official items. If you'd rather rehearse the full clock, give yourself 60 minutes per section; you'll have more time per presented question than the official count-based average, though actual item difficulty and reading time vary.

What we matched, and what we couldn't

We matched the question counts for every scored content area and used NLN's dimension labels and published allocations to organize the set. Biology, for example, has 10 Knowledge, 7 Application, and 3 Interpretation questions here, the same as NLN's scored blueprint. Topics come from NLN's published content outlines. We left out what the NEX dropped from the older PAX, physics and extended geometry, but kept measurement, scale, and supplied-formula problems, because NLN kept those (Technical Manual, §4.2).

Matching counts does not establish equivalent difficulty or validated skill classification. NLN field-tests its questions on applicants before they count; ours haven't been field-tested. Use this set to find what to study, not to predict your score.

Free sources for reviewing each content area

Free sources for reviewing each content area table
Content areaFree sourceWhere to start
Word KnowledgeMerriam-Webster (use the entry linked with each question)Look up each word you missed. Entries show word origins and usage notes, which help you build word-part skills.
Numbers and OperationsOpenStax Prealgebra 2e§4.5 Fractions, §5.2 Decimals, §6.2 Percent applications
MeasurementOpenStax Prealgebra 2e; NIST§7.5 Systems of Measurement; NIST SI prefix table
AlgebraOpenStax Prealgebra 2e§2.1 Language of algebra, §8.3 Solving equations, Linear inequalities
Data and InformationOpenStax Prealgebra 2e§5.5 Averages (mean, median, mode)
BiologyOpenStax Biology 2eStart with §4.3 Eukaryotic Cells and §12.2 Punnett squares
Human Anatomy and Human PhysiologyOpenStax Anatomy and Physiology 2eStart with §1.6 Anatomical terminology and §1.5 Homeostasis
ChemistryOpenStax Chemistry 2e§2.3 Atomic structure, §7.1 Ionic bonding, §14.2 pH
HealthCDC and WHOCDC handwashing, CDC sleep, WHO definition of health

All of these are free to read online without an account.

NLN NEX practice test FAQ

Are these real NEX questions?

No. We wrote every question and passage from NLN's published content outlines. These are original practice items, not official, leaked, or recalled exam questions; no NLN review is claimed.

Can I use a calculator on the NEX?

Yes. NLN's technical manual says the testing platform has a built-in calculator (Technical Manual, §4.2). If you test online through Proctor360, NLN's March 2026 candidate guide lists only four allowed items: a basic four-function calculator, a dry-erase board no larger than 8.5 × 11 inches, a dry-erase marker, and an eraser (NLN Proctor360 guide). If you test in person, ask your school or testing site what it provides.

What NEX score do I need?

NLN doesn't set a passing score; your nursing program does (NLN Student Resources FAQ).

Is the NEX the same as the PAX?

No. NLN released the NEX on February 11, 2024, as the update to the PAX (Technical Brief, p. 2). NLN removed physics and extended geometry, added more unit conversions, and added a Data and Information area to Math (Technical Manual, §4.2). Old PAX materials still overlap, but they won't match the current topic mix.

Sources and how we built this test

By the Castleport Test Prep Editorial Team.

Official NLN sources

How we built and checked this set

We wrote every question and passage ourselves, using NLN's published content outlines for topics and NLN's scored counts for the number of questions in each content area and skill. Each explanation links a source for the fact or rule behind its answer, or points to its original fictional reading passage. The sources include OpenStax textbooks; U.S. government agencies such as the CDC, NIH, NIST, NOAA, the USDA Forest Service, and GPS.gov; the World Health Organization; Merriam-Webster; and historical collection sources. Tables labeled hypothetical, and the library in Passage 5, are made up for practice.

This resource was developed and source-checked with AI assistance. The questions, answer choices, and explanations were checked together, and the numerical answers were recalculated. That is not a documented nurse-educator, clinician, or NLN review, and it does not establish calibrated difficulty or predict an admissions result. Our editorial standards explain that distinction.

Found an error? Report a correction and include this page's URL and the question number. Do not send real or recalled exam questions.

Last verified: September 22, 2026. This date covers the cited exam structure, content allocations, score-report context, institution-set cut scores, calculator and route-specific material rules, and the teaching sources used for this version. It does not represent a test of your testing site's arrangements or a professional review.

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