PSAT Math Multiple-Choice Question 234: Answer and Explanation

Question: 234

A random follow-up survey was administered to 500 of the respondents in District C. They were asked if they planned to vote in the next election. The follow-up survey results were 218 said they planned to vote, 174 said they did not plan to vote, and 108 said they were unsure. Based on the data from both the initial survey and the follow-up survey, which of the following is most likely an accurate statement?

• A. Approximately 19,000 people in District C who support a ban on fracking can be expected to vote in the next election.
• B. Approximately 21,000 people in District C who support a ban on fracking can be expected to vote in the next election.
• C. Approximately 43,000 people in District C who support a ban on fracking can be expected to vote in the next election.
• D. Approximately 48,000 people in District C who support a ban on fracking can be expected to vote in the next election.

Correct Answer: A

Explanation:

A

Difficulty: Medium

Category: Problem Solving and Data Analysis/Statistics and Probability

Getting to the Answer: Scan the answer choices quickly to narrow down the amount of information in the table that you need to analyze. Each choice makes a statement about people from District C who support a ban on fracking that can be expected to vote in the next election. To extrapolate from the follow-up survey sample, multiply the fraction of people from the follow-up survey who plan to vote in the upcoming election by the number of people in District C who support a ban on fracking (43,228) to get 18,847.408, or approximately 19,000 people. Choice (A) is correct.