Educerie · SAT · Reading and Writing
Information and Ideas · II.3 Command of evidence: quantitative
What you must be able to do
| You must be able to | What it looks like on the test |
|---|---|
| Read a value accurately off a table or graph | Axis labels, units, which series is which |
| Judge relevance, not just accuracy | Three options are accurate and irrelevant |
| Complete a sentence with data | …most effectively uses data from the graph to complete the statement |
| Spot the reversed or mismatched reading | The commonest wrong option after irrelevance |
1The idea in one paragraph
Two filters, and students only apply the first. An option must be accurate — a true reading of the figure — and relevant — it must support the specific claim in the sentence. The test builds three options that pass the first filter and fail the second, because being right about the graph feels like being right. Accuracy is the entry requirement, not the answer.
Read the figure before you read the options: title, axis labels, units, and what each bar, line or column stands for. Thirty seconds there saves you the question.
2Read the furniture first
Title — what the figure is of. Axis labels and units — percentages or counts, thousands or millions, per year or cumulative. The key — which series is which, and whether two lines use different scales. The range — what years, which groups, and what is not shown.
Half of quantitative questions are decided by units. An option that swaps percentage for number, or a share of a group for a share of the whole, is wrong no matter how confidently it reads.
3The claim decides which number matters
The sentence you are completing usually contains a comparison word: higher than, unlike, declined while, only. That word tells you which two values to look at.
Unlike the coastal sites, the inland sites recorded their highest rainfall after 1990: ______
The claim needs a contrast between coastal and inland and a post-1990 peak inland. An option giving the inland peak alone is accurate and incomplete. An option comparing two coastal sites is accurate and irrelevant. The claim names what the evidence must contain.
4The four families of wrong option
| Family | What it does |
|---|---|
| Accurate, irrelevant | A true reading that has nothing to do with the claim |
| Half the comparison | Gives one side of a two-sided claim |
| Reversed | Swaps the two groups, or the direction of change |
| Beyond the figure | Asserts something the figure does not show — a cause, a trend after the last year, a group not plotted |
That last one matters. A graph shows what, never why. An option explaining a cause is outside the figure and wrong even if the explanation is sensible.
5Trend questions
When the claim is about a trend, check the whole series rather than the endpoints. A line that falls, rises and falls again has not simply declined, and an option describing it as a steady decline is inaccurate even though the last value is below the first.
Watch for the difference between rate of increase and amount: a quantity can grow every year while the rate of growth slows, and both statements are readable off the same line.
6Tables are graphs with the reading already done
Table questions are usually easier and are lost to carelessness: wrong row, wrong column, wrong year. Put a finger on the row before you read the number, and check the column heading twice when two columns have similar names.
Where points are lost
- Reading the options before the figure. You will accept the first accurate one.
- Missing the units, or mixing a percentage with a count.
- Answering half a two-sided claim.
- Reversing two groups that sit next to each other in the key.
- Explaining a cause the figure cannot show.
- Judging a trend from the endpoints of a line that moves in between.
- Trusting the visual impression on a bar chart whose axis does not start at zero.
Read it right
- Read the figure's furniture: title, axes, units, key, range.
- Read the claim and underline the comparison it makes.
- Decide which two numbers settle it.
- Check each option for accuracy first, then for relevance to that claim.
- Reject anything the figure cannot show.
Try it
Use this table for all three questions.
Mean annual rainfall, four monitoring stations, mm
| Station | 1971–1990 | 1991–2010 | 2011–2020 |
|---|---|---|---|
| Coastal A | 1,180 | 1,145 | 1,090 |
| Coastal B | 1,240 | 1,190 | 1,205 |
| Inland C | 610 | 690 | 705 |
| Inland D | 585 | 640 | 720 |
Q1. A student notes that the two inland stations, unlike the coastal ones, recorded their highest mean rainfall in the most recent period: ______
Which choice most effectively uses data from the table to complete the statement?
A) Inland D recorded 720 mm in 2011–2020, its highest of the three periods. B) Coastal A's mean rainfall fell in every period, from 1,180 mm to 1,090 mm. C) Inland C and Inland D peaked in 2011–2020, at 705 mm and 720 mm, while both coastal stations peaked in 1971–1990. D) Inland D's mean rainfall rose by 135 mm between 1971–1990 and 2011–2020.
Q2. A researcher claims that the coastal stations did not decline uniformly. ______
Which choice most effectively uses data from the table to support the claim?
A) Coastal A fell from 1,180 mm to 1,090 mm across the three periods. B) Coastal B fell to 1,190 mm and then rose to 1,205 mm, while Coastal A fell in both periods. C) Both coastal stations recorded more rainfall than either inland station in every period. D) Coastal B recorded the highest mean rainfall of any station in 1971–1990.
Q3. A student wants to show that the gap between the wettest coastal station and the driest inland station narrowed over the period covered. ______
A) In 1971–1990 the gap between Coastal B and Inland D was 655 mm; in 2011–2020 it was 485 mm. B) Inland D rose from 585 mm to 720 mm over the period. C) Coastal B recorded 1,240 mm in 1971–1990 and 1,205 mm in 2011–2020. D) Rainfall at the inland stations increased because the coastal stations became drier.
In one breath
An option has to pass two filters and the test only makes the first one feel important: it must be an accurate reading of the figure and it must support the claim in front of you. Read the furniture first — title, axes, units, key — then underline the comparison the claim makes and decide which two numbers settle it. A figure shows what happened, never why, so any option offering a cause is out before you check the arithmetic.
Answers
Q1. C. both halves of the contrast, with figures The claim is two-sided — inland peaked recently, coastal did not — and only C carries both. A and D are accurate and give one side only. B is accurate, is about the coastal side alone, and would support a different claim.
Q2. B. one coastal station reversed, the other did not "Did not decline uniformly" needs the difference between the two coastal stations shown, and Coastal B's rise in the last period against Coastal A's continued fall is exactly that. A shows a uniform decline at one station, which is the opposite. C and D are accurate readings about coastal-versus-inland and about a single maximum — irrelevant to uniformity.
Q3. A. the gap itself, at both ends of the period Wettest coastal is Coastal B, driest inland is Inland D, and 655 mm narrowing to 485 mm is the claim. B and C each give one station's change and leave the reader to compute the gap. D asserts a cause the table cannot show, and reverses it as well.
Educerie · written from the published College Board* Assessment Framework for the Digital SAT Suite *(Information and Ideas, skill/knowledge testing point "Command of Evidence — Quantitative"). All data, options and explanations are original Educerie text; the figures above are invented for teaching and are not measurements. Last reviewed 12 September 2026.
Check your understanding
The main ideas of this note. Tick each one you could do now, in an exam, without looking back up. Anything you cannot tick yet is the part to read again.