PSAT Math Multiple-Choice Practice Question 211

Correct Answer: D

Explanation:

D

Difficulty: Medium

Category: Problem Solving and Data Analysis/Statistics and Probability

Getting to the Answer: The two variables are certainly correlated—as one goes up, the other goes up. A linear regression model would fit the data fairly well, so you can eliminate (C). The spending is graphed on the x-axis, so it is the independent variable and therefore does not depend on the GDP, graphed on the y-axis, so you can eliminate (B) as well. The data does show that as spending on students increases, so does the GDP, but this is simply correlation, not causation. Without additional data, no statements can be made about whether spending more on students is the reason for the increased GDP, so (D) is correct.