SAT Reading and Writing: Command of Evidence — Quantitative
Master the essential skill of interpreting graphs, charts, and tables to identify quantitative evidence that supports claims—combining data literacy with critical reading for SAT success.
By NUM8ERS SAT Prep Team | Updated October 2025
What is Command of Evidence: Quantitative?
Command of Evidence: Quantitative questions test your ability to interpret data from graphs, charts, and tables and use that numerical information to complete statements that support specific claims. Unlike pure math questions, these combine reading comprehension with data analysis—you must understand the argument in the passage text and identify which quantitative evidence best supports it.
These questions appear with various data visualizations (bar graphs, line graphs, tables, scatter plots) alongside a short passage. Your task is to select the answer choice that most effectively uses data from the graphic to complete a sentence or support an assertion.
The correct answer must contain factually accurate data from the graphic that directly supports the specific claim being made in the passage.
Understanding Data Visualizations on the SAT
📊 Bar Graphs
Use vertical or horizontal bars to compare quantities across categories. Read labels carefully and compare bar heights/lengths to determine relative values.
📈 Line Graphs
Show trends and changes over time. Look for slopes (increasing/decreasing), points where lines cross, and overall patterns across time periods.
📋 Tables
Organize data in rows and columns. Carefully match row headers with column headers to locate specific data points. Watch for units and totals.
⚫ Scatter Plots
Display relationships between two variables. Look for correlations (positive, negative, or none) and outliers that deviate from overall patterns.
Typical Question Format:
[Passage providing context about a topic] ...The main contributors to [phenomenon] have been [example], whose [measure] went from ______
Which choice most effectively uses data from the graph to complete the statement?
The Four-Step Quantitative Evidence Strategy
Skim the Graph/Table
Quickly scan the title, axes labels, units, and legend/key. Don't analyze data yet—just familiarize yourself with what information is available and how it's organized.
Read and Understand the Argument
Focus on the passage text. Identify the claim or assertion being made. What specific data will support this claim? Sometimes the text explicitly tells you what to look for (e.g., "Algeria in 1970 vs 2020"); other times you'll need to understand the general argument.
Validate the Choices (True vs. False)
Check each answer choice against the data. Are the numbers accurate? Eliminate any choices that contain false data. If all remaining choices are factually true, proceed to Step 4.
Find the Best Evidence
Among the true statements, identify which one most directly supports the argument. Only one choice will provide relevant, effective evidence that completes the sentence logically and strengthens the claim.
Top Tips for Quantitative Evidence Questions
- Find the story: Data tells a story—look for trends, comparisons, dramatic changes, or significant differences that the passage emphasizes.
- Use your finger/cursor: When reading complex graphs, place your finger or cursor on the exact data point to avoid eye drift and reading errors.
- Check true vs. false first: If one wrong answer is false, usually all wrong answers are false. Eliminate inaccurate data immediately.
- Don't get overwhelmed: Graphs contain more data than you need. Focus only on what the passage directs you to find.
- Match units and scales: Pay attention to percentages vs. raw numbers, thousands vs. millions, and axis scales that don't start at zero.
- Be flexible with ranges: The answer might express data as approximate ranges rather than exact numbers (e.g., "approximately 40%" instead of "39.7%").
Worked Example 1: Line Graph — Urbanization Trends
Context & Graph Description:
The share of the world's population living in cities has increased dramatically since 1970, but this change has not been uniform. France and Japan, for example, were already heavily urbanized in 1970, with 70% or more of the population living in cities. The main contributors to the world's urbanization since 1970 have been countries like Algeria, whose population went from ______
Key data points:
• Algeria: ~40% (1970) → ~75% (2020)
• France: ~72% (1970) → ~81% (2020)
• Japan: ~72% (1970) → ~92% (2020)
• Brazil: ~56% (1970) → ~87% (2020)
Which choice most effectively uses data from the graph to complete the statement?
✓ Step-by-Step Solution:
Step 1 — Skim the graph: Line graph showing urbanization trends for four countries from 1970-2020. Different markers for each country.
Step 2 — Read the argument: The passage claims that countries like Algeria (already mentioned as heavily urbanized in 1970 contrast) were main contributors to world urbanization growth. We need Algeria's data specifically.
Step 3 — Validate choices: Check each answer for accuracy by locating Algeria's triangle markers:
- Choice A: Says Algeria went 40% → 70%. The graph shows 40% → ~75%, not 70%. ✗ False data.
- Choice B: These numbers (56% → 87%) match Brazil, not Algeria. ✗ Wrong country.
- Choice C: "Approximately 40%" → "approximately 75%" matches Algeria's triangle markers accurately. ✓ True data.
- Choice D: These numbers (72% → 92%) match Japan, which the passage says was already heavily urbanized. ✗ Wrong country; contradicts argument.
Step 4 — Find best evidence: Only Choice C is factually accurate AND supports the argument that Algeria (starting at low urbanization) was a major contributor to growth.
Worked Example 2: Bar Graph — Energy Consumption
Context & Graph Description:
Global energy consumption patterns vary significantly by source. While fossil fuels remain dominant, renewable energy sources have grown substantially. According to recent data, the energy source with the greatest absolute consumption worldwide is ______
Bar heights:
• Oil: 175 EJ
• Natural Gas: 135 EJ
• Coal: 155 EJ
• Nuclear: 30 EJ
• Renewables: 85 EJ
Which choice most effectively uses data from the graph to complete the statement?
✓ Analysis:
- Claim focus: "Greatest absolute consumption" = highest bar on the graph.
- Step 3 — Validate data: Compare bar heights:
- Oil: 175 EJ (tallest bar) ✓
- Coal: 155 EJ (second tallest)
- Natural Gas: 135 EJ
- Renewables: 85 EJ
- Nuclear: 30 EJ (shortest)
- Choice A: Correctly identifies oil as highest at ~175 EJ. ✓ True & relevant.
- Choice B: Renewables are only 85 EJ, not the greatest. Also adds interpretation ("shift") not supported by single-year data. ✗
- Choice C: Coal is second-highest, not greatest. ✗ Inaccurate to claim.
- Choice D: Nuclear is the lowest consumption. ✗ Opposite of claim.
Worked Example 3: Table — Employment Statistics
Context & Table Description:
Automation has affected various occupations differently. A 2024 labor market survey examined employment changes in four sectors over a five-year period. The data suggest that the occupation experiencing the most dramatic decline was ______
| Occupation | 2019 Employment | 2024 Employment | % Change |
|---|---|---|---|
| Data Entry Clerks | 425,000 | 290,000 | -31.8% |
| Manufacturing Workers | 1,200,000 | 980,000 | -18.3% |
| Software Developers | 780,000 | 925,000 | +18.6% |
| Retail Salespeople | 3,500,000 | 3,150,000 | -10.0% |
Which choice most effectively uses data from the table to complete the statement?
✓ Analysis:
- Claim focus: "Most dramatic decline" = greatest percentage decrease.
- Key distinction: "Dramatic" suggests proportional change (%), not absolute numbers.
- All data is accurate, so we move to Step 4—which evidence best supports "most dramatic decline"?
- Choice A: -31.8% is the largest percentage decline. ✓ Best evidence.
- Choice B: Manufacturing lost 220,000 jobs (-18.3%), but that's not the most dramatic. ✗
- Choice C: Retail lost 350,000 jobs (largest absolute loss), but only -10.0%—not most dramatic proportionally. ✗
- Choice D: Software developers grew—opposite of decline. ✗ Contradicts claim.
Worked Example 4: Line Graph — Comparing Multiple Variables
Context & Graph Description:
Climate scientists tracked average monthly temperatures and precipitation levels in Phoenix, Arizona throughout 2024. Researchers noted that the relationship between temperature and rainfall shows ______
Pattern:
• Temperature peaks in July-August (~105°F)
• Precipitation peaks in July-August (~3.5 inches)
• Winter months show low temps (~65°F) and low precipitation (~0.5 inches)
• Both variables follow similar seasonal patterns
Which choice most effectively uses data from the graph to complete the statement?
✓ Analysis:
- Step 3 — Validate: Check each claim against the graph pattern.
- Choice A: Says highest precipitation occurs during coolest months—FALSE. Graph shows both peak together in summer. ✗
- Choice B: Both variables peak July-August (summer)—TRUE. This is a positive correlation. ✓
- Choice C: There IS a clear seasonal pattern—FALSE claim. ✗
- Choice D: Temperatures vary from ~65°F to ~105°F—not stable. FALSE. ✗
Quick Example 5: Scatter Plot — Study Hours vs. Test Scores
A study examined the relationship between weekly study time and exam performance among 50 students. The scatter plot shows study hours (x-axis, 0-20 hours) versus exam scores (y-axis, 0-100 points). Data points show a clear upward trend from bottom-left to top-right, with students studying 2-5 hours clustering around 60-70 points and students studying 15-18 hours clustering around 90-95 points.
Claim: The data suggest that increased study time is associated with higher exam scores.
Which choice provides the best evidence?
Why? The correct answer compares two data ranges showing the relationship between study time and scores. The wrong answer provides accurate data but only one point—it doesn't demonstrate the association the claim describes. For correlation claims, you need to show the pattern, not just a single data point.
Common Pitfalls and How to Avoid Them
- Reading the wrong data point: Use your finger/cursor to track exact locations. Check row AND column headers on tables.
- Confusing absolute vs. proportional change: "Dramatic" or "significant" often refers to percentages, not raw numbers. A 50% drop is more dramatic than losing 100 workers from 1,000,000.
- Choosing true but irrelevant data: Just because data is accurate doesn't mean it supports the specific claim. Stay focused on the argument.
- Ignoring units and scales: Is it thousands or millions? Percentages or raw counts? Check axis labels carefully.
- Missing the "story": The passage emphasizes certain patterns—your evidence should reinforce that story, not introduce new angles.
- Assuming trends beyond the data: If a graph shows 2010-2020, don't select an answer that claims what happened in 2025.
- Overlooking graph keys/legends: Multi-line or multi-bar graphs require careful attention to which line/color represents which variable.
Two Types of Incorrect Answers
Pro Tip: Usually, if one wrong answer is false, all wrong answers are false. If one wrong answer is true (but irrelevant), all wrong answers are true. Recognizing this pattern early helps you adjust your elimination strategy.
Key Takeaways
- Quantitative evidence questions combine reading comprehension with data interpretation—you must understand the argument AND read the data accurately.
- Always use the four-step strategy: (1) skim the graph, (2) read and understand the argument, (3) validate choices as true or false, (4) find the best evidence.
- Use your finger or cursor to avoid eye drift when reading complex graphs with multiple data points.
- Don't get overwhelmed by data—focus only on what the passage directs you to find.
- Pay attention to units, scales, and keys—misreading these causes avoidable errors.
- Distinguish between absolute changes (raw numbers) and proportional changes (percentages).
- True data doesn't automatically mean effective evidence—it must directly support the specific claim.
- Familiarize yourself with common graph types: bar graphs (comparisons), line graphs (trends over time), tables (organized data), and scatter plots (relationships).
Study & Practice Strategy
📚 Build Data Literacy
- Practice reading graphs and tables from news articles, scientific journals, and textbooks daily.
- For each data visualization you encounter, practice identifying the title, axes, units, and key before analyzing data.
- Create "data stories"—verbally summarize what graphs show in 1-2 sentences.
🎯 Practice Systematically
- Time yourself: aim for 60-75 seconds per quantitative evidence question.
- Practice identifying "true but irrelevant" wrong answers—this is the trickiest skill.
- Use Khan Academy, College Board Official Practice, and UWorld for authentic question types.
💡 Avoid Common Mistakes
- Always check units and scales—many traps involve misreading axis labels.
- For multi-variable graphs, use legends/keys systematically to avoid mixing up data series.
- Review every wrong answer to understand whether you misread data or chose irrelevant evidence.
📖 Related SAT Skills
- Command of Evidence: Textual
- Central Ideas and Details
- Inference Questions
- SAT Math: Problem Solving & Data Analysis
🎓 NUM8ERS Quantitative Evidence Excellence
At NUM8ERS Dubai, we train students to master the unique challenge of quantitative evidence questions through targeted practice with authentic SAT data visualizations. Our systematic approach emphasizes the four-step strategy, pattern recognition in graphs and tables, and the critical skill of distinguishing accurate-but-irrelevant data from truly effective evidence. Students develop confidence interpreting complex data under time pressure—a skill that serves them on the SAT and in university coursework.
Our instructors combine expertise in data literacy with deep knowledge of SAT question design, helping Dubai students achieve top scores on Information and Ideas questions. Whether you're strengthening foundational graph-reading skills or refining advanced test-taking strategies, NUM8ERS provides personalized support for SAT Reading and Writing excellence.
⚡ Test Day Pro Tips
- Budget your time: Spend 15-20 seconds reading the graph, 20-25 seconds on the passage, and 20-30 seconds evaluating choices.
- Don't overthink: If data clearly matches and supports the claim, select it confidently—don't second-guess with complex reasoning.
- Watch for axis tricks: Axes that don't start at zero, logarithmic scales, or reversed scales are common sources of misinterpretation.
- Approximations are okay: SAT answers often use "approximately" or ranges—you don't need exact precision.
- Context matters: Always read the passage before analyzing data. The argument tells you what to look for and what "counts" as relevant.
- Digital test advantage: Use the zoom feature if graph text is small, and use your cursor as a precise tracking tool.
Graph Reading Formulas & Calculations
While you won't need to perform complex calculations, understanding these basic relationships helps you interpret quantitative evidence:
Percent Change:
Example: From 400 to 320 → \(\frac{320-400}{400} \times 100\% = -20\%\)
Rate of Change (Slope):
Useful for line graphs showing trends over time
Reading Proportions:
Important for pie charts and survey data