GRE Chart Interpretation Questions Practice Questions with Answers

Concept Explanation

GRE Chart Interpretation Questions are a specific subset of the Quantitative Reasoning section that require you to analyze data presented in tables, bar graphs, line graphs, or pie charts to solve mathematical problems. These questions evaluate your ability to synthesize information from visual representations and apply arithmetic, algebraic, or statistical operations to that data. Often, you will need to calculate percentages, find averages, or identify trends across multiple years or categories. Success in this area relies on carefully reading the axes, legends, and units provided, as many errors occur from misinterpreting the scale or failing to notice that numbers are represented in thousands or millions.

When preparing for your exam, utilizing a GRE Prep hub can help you organize your study of these visual data sets. Most questions involve multi-step calculations, such as finding a percentage increase between two years shown on a bar graph. You must also be prepared for "Data Interpretation" sets, where a single group of charts serves as the basis for three or four consecutive questions. For more specialized practice in other areas, you might find the AI Question Generator useful for creating custom drills based on your weak points.

Solved Examples

Below are three examples of how to approach GRE Chart Interpretation Questions with detailed step-by-step logic.

1. Example 1: Percentage Increase
   A bar chart shows that Company X's revenue was $400,000 in 2020 and $500,000 in 2021. What was the percent increase in revenue from 2020 to 2021?
   1. Identify the initial value (2020) as $400,000 and the final value (2021) as $500,000.
   2. Calculate the absolute change: $$500,000 - 400,000 = 100,000$$
   3. Divide the change by the original value: $$\frac{100,000}{400,000} = 0.25$$
   4. Convert to a percentage: $0.25 \times 100 = 25\%$.
2. Example 2: Pie Chart Allocation
   A city budget of $12 million is represented in a pie chart. If the "Education" sector accounts for $15\%$ of the budget and "Public Safety" accounts for $25\%$, how much more money is spent on Public Safety than Education?
   1. Calculate the dollar amount for Education: $0.15 \times 12,000,000 = 1,800,000$.
   2. Calculate the dollar amount for Public Safety: $0.25 \times 12,000,000 = 3,000,000$.
   3. Find the difference: $$3,000,000 - 1,800,000 = 1,200,000$$
   4. The city spends $1.2 million more on Public Safety.
3. Example 3: Reading Multiple Axes
   A dual-axis line graph shows the number of employees (left axis) and total production units (right axis) over 5 years. In Year 3, there are 50 employees and 10,000 units produced. What is the average production per employee in Year 3?
   1. Locate Year 3 on the horizontal axis.
   2. Trace to the employee line and read the left axis: 50 employees.
   3. Trace to the production line and read the right axis: 10,000 units.
   4. Divide units by employees: $$\frac{10,000}{50} = 200 \text{ units per employee}$$

Practice Questions

Test your skills with the following GRE Chart Interpretation Questions. Assume all charts are drawn to scale unless otherwise noted.

1. A table lists the population of five cities. City A: 120,000; City B: 80,000; City C: 150,000; City D: 200,000; City E: 50,000. What is the average (arithmetic mean) population of the five cities?

2. A bar graph shows annual sales for a store: Year 1: $200,000; Year 2: $250,000; Year 3: $225,000. What is the ratio of Year 2 sales to Year 3 sales?

3. In a pie chart showing a student's monthly expenses, "Rent" is a sector with a central angle of $108^{\circ}$. What percentage of the student's total expenses is spent on rent?

4. A line graph tracks the price of a stock over 4 days: Day 1: $10; Day 2: $12; Day 3: $9; Day 4: $11. Between which two consecutive days was the greatest absolute change in price?

5. Referring to the stock in Question 4, what was the average price over the 4-day period?

6. A table shows the number of cars sold by three dealers (X, Y, Z) in two colors (Red, Blue). Dealer X: 10 Red, 20 Blue. Dealer Y: 15 Red, 15 Blue. Dealer Z: 20 Red, 10 Blue. What percentage of all Red cars were sold by Dealer Z?

7. A bar graph indicates that in 2010, a library had 5,000 books, and in 2020, it had 8,500 books. What is the percent increase in the number of books over this decade?

8. In a group of 200 people, a chart shows 40% are under age 30, 50% are between 30 and 60, and the rest are over 60. How many people are over age 60?

9. A scatter plot shows the relationship between hours studied and test scores. If a student who studied 5 hours scored 80 and a student who studied 10 hours scored 90, what is the slope of the line connecting these two data points?

10. A table shows the monthly rainfall in inches: Jan (2.5), Feb (3.0), Mar (4.5). If the total rainfall for the first four months of the year was 12.0 inches, how much rain fell in April?

Answers & Explanations

Review the detailed solutions below to understand the logic behind each practice question.

1. Answer: 120,000
   Sum the populations: $120,000 + 80,000 + 150,000 + 200,000 + 50,000 = 600,000$. Divide by the number of cities: $600,000 / 5 = 120,000$.
2. Answer: 10:9
   Year 2 sales are $250,000 and Year 3 sales are $225,000. The ratio is $250,000 : 225,000$. Dividing both by 25,000 simplifies the ratio to $10:9$.
3. Answer: 30%
   A full circle has $360^{\circ}$. The percentage is calculated as $\frac{108}{360}$. Simplifying the fraction: $\frac{108}{360} = 0.3$, which is $30\%$.
4. Answer: Day 2 to Day 3
   Changes: Day 1-2 is $|12-10| = 2$; Day 2-3 is $|9-12| = 3$; Day 3-4 is $|11-9| = 2$. The greatest change is 3 between Day 2 and Day 3.
5. Answer: $10.50
   Sum the prices: $10 + 12 + 9 + 11 = 42$. Divide by 4 days: $42 / 4 = 10.5$.
6. Answer: 44.4% (or 4/9)
   Total Red cars = $10 + 15 + 20 = 45$. Dealer Z sold 20 Red cars. The percentage is $(20/45) \times 100 \approx 44.4\%$.
7. Answer: 70%
   Increase = $8,500 - 5,000 = 3,500$. Percent increase = $(3,500 / 5,000) \times 100 = 0.7 \times 100 = 70\%$.
8. Answer: 20
   Percentage over 60 = $100\% - (40\% + 50\%) = 10\%$. Number of people = $0.10 \times 200 = 20$.
9. Answer: 2
   Slope $m = \frac{y_2 - y_1}{x_2 - x_1}$. Here, $\frac{90 - 80}{10 - 5} = \frac{10}{5} = 2$.
10. Answer: 2.0 inches
    Sum of Jan-Mar = $2.5 + 3.0 + 4.5 = 10.0$. April rainfall = $12.0 - 10.0 = 2.0$.

1. If a pie chart sector representing "Utilities" has an angle of \( 72^{\circ} \), what fraction of the total budget does this represent?

• A1/4
• B1/5
• C1/6
• D1/3

Frequently Asked Questions

What is the best way to avoid simple mistakes on GRE data interpretation?

Always double-check the units on the axes and the legend to ensure you aren't missing factors like "in millions" or "per 100,000 people." Additionally, re-read the question to confirm whether it asks for a total value, a difference, or a percentage change.

How much time should I spend on a single chart interpretation set?

Since these questions usually come in sets of three or four, you should aim to spend about 1.5 to 2 minutes per question. Spending more than 8 minutes on a single data set can jeopardize your ability to finish the rest of the Quantitative section.

Do I need to use complex statistical formulas for these questions?

No, the GRE focuses on basic statistical concepts like mean, median, mode, range, and standard deviation trends. You will not need to calculate complex regressions, but you should understand how to find the average of data points listed in a table.

Can I use the on-screen calculator for chart questions?

Yes, the on-screen calculator is available and highly recommended for multi-step percentage calculations or large sums. For more practice with the interface, you can use an AI Exam Simulator to mimic the testing environment.

What are common "traps" in GRE graph questions?

Common traps include asking for a percentage increase when the options provide the absolute increase, or providing data for one category while asking about the "rest" of the group. Always verify if the question refers to a specific sub-group or the entire data set.