Quiz 1 — Reading Science

The Guide

What a science question is made of

Almost every question on the GED Science test comes attached to something you have to read or look at: a short passage, a table, a graph, or a diagram. That attached thing has a name — the stimulus — and the question is about it.

This is good news. It means the answer is usually right in front of you. You are not being asked to remember a science class from years ago.

It also causes the most common mistake on the test. An answer choice can be completely true about the world and still be the wrong answer, because the passage never said it. The question is not what do you know? It is what does this say, and what follows from it?

Three kinds of question

What does it say. Usually signaled by according to the passage or according to the table. The answer is written down somewhere. Your job is to find the line.
What does it mean. Usually signaled by based on the data or the results suggest. The answer is not written down, but it follows directly from two or three things that are.
What would happen. Usually a new situation: a student repeats the experiment using…. You take the rule from the passage and apply it somewhere new.

The order that saves time. Give the stimulus about ten seconds first — what is this about, what are the units, what do the axes say. Then read the question. Then go back and find the exact line or number. Reading the whole passage closely before you know what you are looking for costs minutes you do not have.

Small words carry the trap. Watch all, only, always, never, every, most, average. An average of 74 does not mean everyone scored 74. A group that did better on average did not necessarily have a single person who beat every person in the other group. Strong words make an answer easy to disprove, so a choice containing all or never is wrong more often than it is right.

Worked Examples

Two questions, worked through

Passage

A gardener wanted to know whether a new fertilizer helped tomato plants. She grew twenty plants in the same soil, with the same amount of sun and water. Ten received the fertilizer. Ten did not. After eight weeks, the fertilized plants had produced an average of 14 tomatoes each. The others averaged 9.

Example 1. According to the passage, how many plants did not receive the fertilizer?

The phrase according to the passage tells you the answer is written down. Do not calculate anything. Find the sentence: "Ten received the fertilizer. Ten did not."

Answer: ten. The whole job was locating one word.

Example 2. Which conclusion do the results best support?

Now the answer is not written down. It has to follow from the numbers, and it has to stay inside them. "In this experiment, the fertilized plants produced more tomatoes on average" is supported: 14 is more than 9, and it says on average, and it says in this experiment.

"This fertilizer works on all vegetables" is not supported. The gardener tested tomatoes. Nothing here says a word about lettuce. The choice reaches past the evidence, and reaching past the evidence is how wrong answers are built.

Answer: stay inside the numbers. Support means the data reaches that far and no farther.

The Quiz

Ten questions

Answer all ten, then press the button at the bottom. Nothing is timed. If you are unsure between two choices, mark the one you can point to a line for.

Passage A — questions 1 to 3

Researchers at a community college studied whether eating breakfast affected scores on a morning math quiz. They recruited 120 students. Half were given a free breakfast at 8:00 a.m. The other half were asked not to eat before the 9:00 a.m. quiz. Both groups took the same quiz.

The breakfast group averaged 74 out of 100. The no-breakfast group averaged 68. The following semester the researchers ran the same study with a different group of 120 students and found a similar gap.

1.According to the passage, how many students took part in the first study?

A60
B68
C120
D240

2.Which statement does the passage support?

AEating breakfast makes people smarter.
BEvery student who ate breakfast scored above 68.
CStudents cannot learn without breakfast.
DOn this quiz, the breakfast group scored higher on average than the no-breakfast group.

3.The researchers ran the study again the next semester. What does running it a second time add?

AIt shows the first result was probably not a one-time accident.
BIt proves the result beyond any doubt.
CIt doubles the scores of both groups.
DIt removes the need for a comparison group.

Table — questions 4 and 5

Liquid	Boiling point at sea level (°C)
Water	100
Ethanol	78
Acetone	56
Glycerol	290

4.According to the table, which liquid boils at the lowest temperature?

AWater
BEthanol
CAcetone
DGlycerol

5.A student slowly heats a mixture of water and acetone. Which liquid boils away first, and why?

AAcetone, because it boils at a lower temperature than water.
BWater, because there is more of it.
CGlycerol, because it has the highest boiling point.
DNeither, because mixtures do not boil.

Graph — questions 6 and 7

One plant, measured once a week for six weeks.

6.Between which two weeks did the plant grow the most?

AWeek 1 and week 2
BWeek 3 and week 4
CWeek 4 and week 5
DWeek 5 and week 6

7.Suppose the plant kept growing at the same rate it grew between week 5 and week 6. About how tall would it be at week 7?

AAbout 31 cm
BAbout 62 cm
CAbout 34 cm
DAbout 40 cm

Passage B — questions 8 to 10

A city added a protected bike lane on Main Street in 2022. In 2023, reported bicycle crashes on Main Street were 40 percent lower than in 2021. Over the same period, the number of cyclists counted on Main Street rose by 15 percent. City officials said the lane had made the street safer.

A traffic researcher pointed out that 2023 was also the first full year of a citywide 20-mile-per-hour speed limit.

8.According to the passage, what happened to the number of cyclists on Main Street?

AIt fell by 40 percent.
BIt stayed about the same.
CThe passage does not say.
DIt rose by 15 percent.

9.Which of these is a claim about what the numbers mean, rather than a measurement?

ACrashes were 40 percent lower in 2023 than in 2021.
BCyclist counts rose by 15 percent.
CThe bike lane made the street safer.
DA 20-mile-per-hour speed limit was in effect citywide in 2023.

10.Why does the traffic researcher's point matter?

AAnother change happened at the same time, so the drop in crashes cannot be credited to the bike lane by itself.
BIt proves the bike lane did not help at all.
CIt shows the crash numbers were counted wrong.
DIt shows that more cyclists on a street cause fewer crashes.

Send this line to your teacher

The line records which questions you missed and which answer you chose. That is more useful to your teacher than the score, because it shows where a question went wrong. If a question felt unclear even though you got it right, add its number with a question mark — for example 5? — before you send it.

Score ______ / 10 Missed — write the question number and the letter you chose:
______________________________________________________________

The Key

Answers, and the trap in each one

1. C — 120. The passage says the researchers recruited 120 students, then split them in half. D tempts because a second group of 120 came along the next semester, but the question asked about the first study. A is one of the two halves. B is a score, not a headcount — it was sitting right there in the paragraph, which is exactly why it works as bait.

2. D — the breakfast group scored higher on average. 74 is higher than 68, and both are averages, and both come from this one quiz. The statement reaches exactly as far as the evidence does. B says every. An average of 74 tells you nothing about any single student; someone in that group may have scored 40. A and C are the kind of large true-sounding statements that a study of one quiz cannot support.

3. A — it shows the result was probably not a one-time accident. Repeating an experiment tests whether the result holds, or whether the first run was luck. B goes too far. Science does not deal in proof beyond any doubt, and answer choices that promise it are almost always wrong.

4. C — acetone, at 56 °C. Read down the second column and find the smallest number. D tempts anyone reading quickly, because 290 is the number that stands out. Standing out is not the same as being lowest.

5. A — acetone, because it boils at a lower temperature. Heat the mixture and the liquid with the lower boiling point reaches its boiling point first. This is a what would happen question: the table gives the rule, the question gives a new situation. C names a liquid that is not in the mixture at all. That kind of choice catches people who match words to the table instead of reading the question.

6. B — between week 3 and week 4. The plant went from about 13 cm to about 22 cm, a gain of 9 cm. That is the steepest stretch of the line, and steepest means fastest growth. D tempts because the line is highest there. Highest is not the same as rising fastest — by week 5 the plant is tall but slowing down.

7. C — about 34 cm. From week 5 to week 6 the plant gained about 3 cm, from 28 to 31. One more week at that rate puts it near 34. B doubles 31, which is what happens when you reach for a big number instead of the rate the question named. A is the week 6 height, which would mean no growth at all.

8. D — it rose by 15 percent. Stated outright in the first paragraph. A borrows the 40 percent from the crash sentence. Two numbers in one paragraph, and the wrong one is easy to grab when you are moving fast.

9. C — the bike lane made the street safer. A, B, and D are counts and rules: someone measured them or wrote them into law. C is an interpretation of those counts, offered by officials. Nobody measured "safer." This distinction runs through the whole test. Learn to hear the difference between here is what we counted and here is what we think it means.

10. A — another change happened at the same time. The speed limit and the bike lane arrived together, so the drop in crashes could belong to either, or to both. The researcher is not attacking the lane. He is pointing out that the evidence cannot separate the two causes. B overshoots in the opposite direction. Saying a cause is not proven is not the same as saying it is disproven — and the test loves to offer you that swap.

Your Score

What the number means

10 out of 10	Solid. Check topic 1 on your map and go on to Quiz 2.
8 or 9	Solid. Read the key for the ones you missed, check topic 1, and move on.
6 or 7	Close. Read the whole key, not only your misses. Take this quiz again in a few days before you check the box.
5 or fewer	This one is worth real time, because it pays you back on every other quiz in the series. Reread the Guide, work the two examples again on paper, then come back to the ten.

Look at which ones you missed as well as how many. Misses on 1, 4, and 8 mean the answer was on the page and you did not find it — that is a searching problem, and slowing down fixes it. Misses on 2, 9, and 10 mean you accepted a statement that went further than the evidence — that is a judgment problem, and it is the one the science test cares about most.

The plate for this quiz

Part I's gallery image is one of Orra White Hitchcock's classroom charts, drawn in ink on linen between 1828 and 1840 for geology lectures at Amherst College — poster-sized sheets made to be hung on a wall and read from across a room. She made more than sixty of them. It seemed right to open a quiz about reading science with a picture built to be read.

Image to be placed at deployment. Source: Amherst College Archives and Special Collections, Orra White Hitchcock Classroom Drawings — acdc.amherst.edu. The drawings are old enough to be out of copyright; the college marks its scans as in copyright with educational use permitted, so the credit line should say so.