American Diploma · Digital SAT · Reading and Writing · Information and Ideas
Command of Evidence: Quantitative
Use tables, bar graphs and line graphs to back up a claim: read the data fast, match the claim and not just the numbers, and avoid the true-but-irrelevant trap — with four worked examples and a 10-question quiz.
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What this question type tests
Some Reading and Writing passages on the Digital SAT come with a table, a bar graph or a line graph. Command of Evidence: Quantitative questions ask you to use the numbers to back up a statement in the text. The stem usually sounds like this (in our words): "Which choice most effectively uses data from the table to complete the statement?" or "Which choice most effectively uses data from the graph to illustrate the researcher's claim?"
It is part of the Information and Ideas domain, together with Central Ideas and Details, Command of Evidence — Textual, and Inferences. These four skills together make up about 26% of the scored Reading and Writing questions (12–14 questions across both modules). Like every Reading and Writing question, it has one short passage (25–150 words) and four choices; here the passage simply includes some data as well.
This is not a math question. You only need to read values, compare them, and see a trend (going up, going down, bigger, smaller). The difficulty is logical: often three or even all four choices state numbers that are true. Only one of them proves the point the text is making.
مش كفاية إن الأرقام اللي في الإجابة صح. أغلب الاختيارات بتكون أرقامها صح فعلاً من الجدول! الإجابة الصح هي اللي الأرقام بتاعتها بتثبت الجملة (الـ claim) اللي في القطعة. اقرأ الـ claim الأول، وبعدين دوّر في الجدول على الأرقام اللي تخدمها.
How to read a table or graph fast
- Read the title and labels first (5 seconds). What is being measured? In what units (percent, thousands, minutes)? What are the rows/columns, or the x-axis and y-axis? Which line or bar is which group?
- Do NOT study every number. You do not need all the data — only the part the claim talks about.
- Spot the big picture. Going up or down? Which is highest and lowest? Do two lines move closer together or further apart?
- Now go to the text and find the claim (often the sentence with the blank, or the sentence before it).
| Data form | What to look at | Common claim it supports |
|---|---|---|
| Table | Row and column headings; the units; the two cells the claim compares | "Group A was higher than Group B"; "X rose between two years" |
| Bar graph | Which bar is tallest/shortest; the label on each bar | "X was the most / least common"; "X was greater than Y" |
| Line graph | Direction of each line; where lines cross; the gap between lines | "X increased steadily"; "the gap narrowed"; "X overtook Y" |
Note: on this site, graphs inside practice questions are written as small text tables (for example, "Year | Visitors" with one row per year). Read them exactly as you would read the bars or points of a graph.
The method: match the claim, not just the numbers
- Find the claim and say it simply. "The campaign worked best for plastic and paper." "Sleep falls every year of high school."
- Name what kind of claim it is. A trend (rising/falling)? A comparison between groups? A highest/lowest? A gap that changes? Each type needs a different kind of data.
- Decide what the perfect data sentence must contain. A trend needs at least a start and an end (and sometimes the middle). A comparison needs BOTH groups. "Both X and Y" needs both.
- Check every choice in two steps: (1) Is it accurate according to the data? (2) Does it prove the claim? A choice must pass BOTH tests.
- Choose the one that passes both. If two pass, pick the one that matches the claim more completely.
| The choice is… | Accurate? | Proves the claim? | Result |
|---|---|---|---|
| Misread data (wrong row, wrong year, reversed) | ✗ | — | Eliminate |
| True but irrelevant | ✓ | ✗ | Eliminate (the most common trap) |
| Half of the claim (one group, one year) | ✓ | Only partly | Eliminate |
| Right data for the claim | ✓ | ✓ | Correct |
Worked examples
Worked example 1 — Table, two-part claim
In 2021, the town of Westfield ran a recycling campaign that focused only on paper and plastic. A council report on recycling rates (the percentage of each material that was recycled) concludes that the campaign worked: rates rose the most for the two materials that the campaign targeted.
| Material | 2020 | 2024 |
|---|---|---|
| Paper | 48% | 61% |
| Glass | 35% | 37% |
| Plastic | 12% | 25% |
| Metal | 50% | 52% |
Question: Which choice most effectively uses data from the table to support the report's conclusion?
- A) Metal had the highest recycling rate of any material in 2020.
- B) The recycling rate for plastic rose from 12% in 2020 to 25% in 2024.
- C) Paper and plastic rates each rose by 13 percentage points between 2020 and 2024, while glass and metal rose by only 2 points each.
- D) The recycling rate for paper rose from 48% in 2020 to 52% in 2024.
Answer: C
- A — ✗ Wrong. True but irrelevant. Metal's 50% was indeed the highest in 2020, but the claim is about which materials rose the most.
- B — ✗ Wrong. Half-right. True, and plastic was targeted, but the claim says the two targeted materials rose the MOST — you need both, and a comparison with the others.
- C — ✓ Correct. Paper 48→61 and plastic 12→25 (both +13) against glass 35→37 and metal 50→52 (both +2). It shows the two targeted materials and the comparison with the untargeted ones.
- D — ✗ Wrong. Misread. 52% is metal's 2024 rate; paper rose to 61%.
Worked example 2 — Bar graph, a trend
A health researcher surveyed students at several high schools about their sleep. She claims that the amount students sleep on school nights falls steadily as they move through high school.
| Average sleep on school nights (graph data) | Hours |
|---|---|
| Grade 9 | 7.6 |
| Grade 10 | 7.2 |
| Grade 11 | 6.8 |
| Grade 12 | 6.5 |
Question: Which choice most effectively uses data from the graph to illustrate the researcher's claim?
- A) Average sleep went down every year, from 7.6 hours in grade 9 to 7.2, 6.8, and finally 6.5 hours in grade 12.
- B) Students in grade 12 slept an average of 6.5 hours on school nights.
- C) Students in grade 10 slept more on average than students in grade 11 did.
- D) Students in grade 9 slept an average of less than 7 hours on school nights.
Answer: A
- A — ✓ Correct. A trend claim ("falls steadily") needs the whole pattern. A gives every grade and shows a fall each year.
- B — ✗ Wrong. Half-right. One value cannot show a trend; there is no comparison with earlier grades.
- C — ✗ Wrong. True but too narrow. It compares only two grades, so it does not show a steady fall across all of high school.
- D — ✗ Wrong. Misread. Grade 9 students slept 7.6 hours, which is more than 7.
Worked example 3 — Line graph, two lines
Bright lights near beaches can confuse nesting sea turtles. In 2018, Beach X introduced strict rules that limit lighting at night, while Beach Y introduced no rules. A conservation group argues that the data suggest the lighting rules may have helped turtles: ______
| Turtle nests (graph data) | 2018 | 2020 | 2022 | 2024 |
|---|---|---|---|---|
| Beach X (lighting rules) | 120 | 135 | 160 | 190 |
| Beach Y (no rules) | 210 | 180 | 150 | 125 |
Question: Which choice most effectively uses data from the graph to complete the argument?
- A) Beach Y had more turtle nests than Beach X did in 2018.
- B) both beaches had more than 100 turtle nests in every year shown.
- C) the number of nests at Beach X fell from 190 in 2018 to 120 in 2024.
- D) the number of nests at Beach X rose from 120 in 2018 to 190 in 2024, while the number at Beach Y fell from 210 to 125.
Answer: D
- A — ✗ Wrong. True but irrelevant. The starting numbers do not show any effect of the rules.
- B — ✗ Wrong. True but irrelevant. It shows no difference between the beach with rules and the beach without them.
- C — ✗ Wrong. Reversed. The Beach X line goes UP from 120 to 190, not down.
- D — ✓ Correct. It shows nests rising where rules exist and falling where they do not — a comparison that points to the rules as the difference.
Worked example 4 — Table, comparison between groups
A science museum asked its visitors which type of exhibit they enjoyed most. The museum's director claims that visitors under 18 were much more interested in interactive science exhibits than older visitors were.
| Favorite exhibit type | Visitors under 18 | Visitors 18 and older |
|---|---|---|
| Interactive science | 46% | 22% |
| Paintings | 9% | 31% |
| History objects | 20% | 28% |
| Live demonstrations | 25% | 19% |
Question: Which choice most effectively uses data from the table to support the director's claim?
- A) 31% of visitors aged 18 and older chose paintings as their favorite exhibit type.
- B) 46% of visitors under 18 chose interactive science exhibits, compared with only 22% of visitors aged 18 and older.
- C) Among visitors under 18, interactive science exhibits were chosen more often than any other exhibit type.
- D) 22% of visitors under 18 chose interactive science exhibits.
Answer: B
- A — ✗ Wrong. True but irrelevant. Paintings are not part of the claim.
- B — ✓ Correct. The claim compares two age groups on one exhibit type. B gives the value for both groups and shows the big difference.
- C — ✗ Wrong. Clever trap. It is true, but it compares exhibits WITHIN one age group. The claim compares the two age groups with each other.
- D — ✗ Wrong. Misread: wrong column. 22% is the figure for visitors aged 18 and older.
- True but irrelevant: the numbers are correct, but they are about a different group, year or item than the claim. This is the trap the test uses most.
- Half the claim: one group when the claim compares two; one year when the claim is a trend; one material when the claim says "both".
- Wrong comparison: comparing items inside one group when the claim compares two groups (Worked example 4, choice C).
- Misread data: the wrong row or column, the wrong year, or numbers reversed ("fell from 190 to 120" instead of "rose from 120 to 190").
- Unit traps: percent vs number, thousands vs units, percentage points vs percent.
- Outside information: a choice that states something the data do not show (a cause, a future prediction, a group that is not in the table).
اسأل نفسك سؤالين لكل اختيار: (١) الأرقام دي صح فعلاً من الجدول؟ (٢) الأرقام دي بتثبت الـ claim؟ لازم الإجابة تعدّي الاتنين. أغلب الإجابات الغلط بتعدّي السؤال الأول وتقع في التاني.
- Read the sentence with the claim or the blank FIRST, then look at the data — you will know which numbers matter.
- Glance at the title, units and labels; ignore the rest of the numbers until you need them.
- Label the claim: trend, comparison, highest/lowest, or gap. Then ask what the data sentence must include.
- Eliminate choices that mention a group, year or item the claim does not mention.
- Check the remaining choice against the data, number by number, before you click. This takes 10 seconds and catches misreads.
Practice
- Read the claim first, then only the part of the data it talks about.
- Most wrong answers state TRUE numbers — they just do not prove the claim.
- A trend needs a start and an end; a comparison needs both groups; "both X and Y" needs both.
- Check every number in your choice against the data before you click: wrong row, wrong year and reversed values are common.
- It is a reading question, not a math question: compare, do not calculate more than a simple difference.
All pages in this course
Start here
Craft and Structure
- Words in Context
- High-Value Vocabulary for SAT Reading and Writing
- Text Structure and Purpose
- Cross-Text Connections
Information and Ideas
Standard English Conventions
- Sentence Boundaries
- Commas and Extra Information
- Colons, Dashes and Semicolons
- Subject–Verb Agreement
- Pronouns
- Verb Tense, Aspect and Finiteness
- Modifiers, Parallel Structure and Comparisons
- Plurals and Possessives
Expression of Ideas
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