GRE Graph Questions Practice Questions with Answers

Data interpretation accounts for approximately 25% of the GRE Quantitative Reasoning section, requiring test-takers to extract and analyze information from various visual formats. Solving GRE graph questions involves more than just reading numbers; it requires synthesizing data from bar charts, line graphs, pie charts, and scatter plots to draw logical conclusions. By utilizing an AI Exam Simulator, you can practice these specific visual problems under timed conditions to build both speed and accuracy.

Concept Explanation

GRE graph questions, officially known as Data Interpretation questions, are problems that require you to interpret data presented in tables, charts, or graphs and perform calculations based on that information. These questions test your ability to read scales accurately, understand the relationship between variables, and apply mathematical concepts like percentages, ratios, and averages to real-world data sets. Most sets include 2-3 questions based on the same visual prompt, often requiring you to integrate data from two different sources, such as a bar graph and a corresponding table. Successful students often use a Concept Map to visualize how different data types—like categorical versus continuous variables—are typically represented on the exam. According to ETS, the official administrator of the GRE, these questions assess your skills in modeling and problem-solving rather than just rote computation.

Solved Examples

1. Example 1: Percentage Change in a Bar Chart
   A bar chart shows that the revenue of Company X was $40 million in 2010 and $54 million in 2012. What was the percentage increase in revenue from 2010 to 2012?
   1. Identify the initial value (2010): $V_{initial} = 40$.
   2. Identify the final value (2012): $V_{final} = 54$.
   3. Apply the percentage change formula: $\frac{V_{final} - V_{initial}}{V_{initial}} \times 100$.
   4. Calculate: $\frac{54 - 40}{40} = \frac{14}{40} = 0.35$.
   5. Convert to percentage: $0.35 \times 100 = 35\%$.
2. Example 2: Pie Chart Ratios
   A pie chart representing a city budget of $120 million shows that "Education" accounts for $30\%$ and "Public Safety" accounts for $20\%$. How much more money is spent on Education than Public Safety?
   1. Calculate the dollar amount for Education: $0.30 \times 120 = 36$ million.
   2. Calculate the dollar amount for Public Safety: $0.20 \times 120 = 24$ million.
   3. Find the difference: $36 - 24 = 12$ million.
   4. Alternatively, find the percentage difference first: $30\% - 20\% = 10\%$, then $0.10 \times 120 = 12$ million.
3. Example 3: Weighted Average from a Table
   A table lists three classes. Class A (20 students) has an average score of 80. Class B (30 students) has an average of 70. What is the combined average?
   1. Calculate total points for Class A: $20 \times 80 = 1600$.
   2. Calculate total points for Class B: $30 \times 70 = 2100$.
   3. Sum the total points: $1600 + 2100 = 3700$.
   4. Sum the total number of students: $20 + 30 = 50$.
   5. Divide total points by total students: $\frac{3700}{50} = 74$.

Practice Questions

1. A line graph shows the population of a town growing from 5,000 in Year 1 to 8,000 in Year 5. If the growth was linear, what was the population in Year 3?

2. In a survey of 400 people represented in a pie chart, the "Agree" sector has a central angle of $72^{\circ}$. How many people responded with "Agree"?

3. A bar graph displays monthly rainfall. January: 4 inches; February: 2 inches; March: 6 inches. What is the ratio of February rainfall to the total rainfall for the three months?

4. A scatter plot shows the relationship between hours studied and exam scores. If the line of best fit is $y = 5x + 40$, what is the predicted score for a student who studies for 8 hours?

5. A double bar graph shows Company A's sales were $200k in Q1 and $250k in Q2, while Company B's sales were $150k in Q1 and $300k in Q2. Which company had a higher percentage increase from Q1 to Q2?

6. A table shows the frequency of scores on a 5-point quiz: (Score 1: 2 students), (Score 2: 5 students), (Score 3: 10 students), (Score 4: 8 students), (Score 5: 5 students). What is the median score?

7. A pie chart shows that 40% of a company's expenses are for Salary and 15% are for Rent. If total expenses are $500,000, how much is spent on everything other than Salary and Rent?

8. In a stacked bar chart representing total energy consumption, Coal provides 25 units and Solar provides 15 units out of a total of 100 units. What fraction of the total energy is provided by Solar?

9. A line graph tracking a stock price shows a value of $50 on Monday, $40 on Tuesday, and $60 on Wednesday. What was the average price over the three days?

10. If a bar graph indicates a 20% decrease in production from 2020 to 2021, and the 2021 production was 160 units, what was the production in 2020?

Answers & Explanations

1. Answer: 6,500. The total growth over 4 years (Year 1 to Year 5) is $8,000 - 5,000 = 3,000$. Linear growth means a constant increase per year: $\frac{3,000}{4} = 750$ per year. In Year 3 (2 years after Year 1), the population is $5,000 + (2 \times 750) = 6,500$.
2. Answer: 80. A full circle is $360^{\circ}$. The proportion of the "Agree" sector is $\frac{72}{360} = \frac{1}{5}$. Total people = 400. So, $\frac{1}{5} \times 400 = 80$.
3. Answer: 1:6. Total rainfall = $4 + 2 + 6 = 12$ inches. February rainfall = 2 inches. Ratio = $2:12$, which simplifies to $1:6$.
4. Answer: 80. Using the equation $y = 5x + 40$, substitute $x = 8$: $y = 5(8) + 40 = 40 + 40 = 80$.
5. Answer: Company B. Company A increase: $\frac{250-200}{200} = 25\%$. Company B increase: $\frac{300-150}{150} = 100\%$. Company B is significantly higher.
6. Answer: 3. Total students = $2+5+10+8+5 = 30$. The median is the average of the 15th and 16th values. Cumulative frequencies: Score 1 (up to 2nd), Score 2 (up to 7th), Score 3 (up to 17th). Both the 15th and 16th values fall in the Score 3 category.
7. Answer: $225,000. Salary + Rent = $40\% + 15\% = 55\%$. The remaining expenses = $100\% - 55\% = 45\%$. Calculation: $0.45 \times 500,000 = 225,000$.
8. Answer: 3/20. Solar is 15 units out of 100. Fraction = $\frac{15}{100}$. Dividing both by 5 gives $\frac{3}{20}$.
9. Answer: $50. Average = $\frac{50 + 40 + 60}{3} = \frac{150}{3} = 50$.
10. Answer: 200 units. Let $x$ be the 2020 production. A 20% decrease means $0.80x = 160$. Solving for $x$: $x = \frac{160}{0.80} = 200$.

1. If a pie chart sector has an angle of 90 degrees, what percent of the total does it represent?

• A20%
• B25%
• C30%
• D33.3%

Frequently Asked Questions

How many graph questions are on the GRE?

Typically, each Quantitative Reasoning section contains one Data Interpretation set consisting of a graph or table followed by 3 questions. Since there are two scored quant sections, you can expect around 6 graph-based questions in total.

Do I need to be exact when reading values from a GRE graph?

While you should be as precise as possible, GRE graphs are drawn to scale, and the answer choices are usually spaced far enough apart that a careful estimate will lead you to the correct option. Always check the axes for specific units or scale jumps.

What is the most common mistake in GRE data interpretation?

The most frequent error is misreading the units or failing to notice that a graph represents percentages rather than absolute numbers. Always verify whether the question asks for a "change in value" versus a "percentage change."

Can I use a calculator for these questions?

Yes, the on-screen calculator is available for all Quantitative Reasoning questions, including graph problems. It is highly recommended for multi-step percentage calculations or finding averages from large data sets.

Are the graphs on the GRE always drawn to scale?

Yes, unlike the Geometry section where figures might not be drawn to scale, the Data Interpretation graphs and charts are accurately scaled to allow for visual estimation. This makes it easier to eliminate obviously incorrect answers.