PSAT Math Multiple-Choice Question 739: Answer and Explanation

Question: 739

The researcher is going to pick two of his research subjects from this survey to speak anecdotally about their experiences with social media so that he may have qualitative data to supplement his quantitative data. The first person who will speak will be from the 12–18-year-old group. The second person will be from the 31–45-year-old group. What is the probability (to the nearest hundredth) that the first speaker will primarily use photo sharing and that the second speaker will primarily use text sharing?

• A. 0.02
• B. 0.06
• C. 0.11
• D. 0.13

Correct Answer: D

Explanation:

(D) Take the fractions of the portion of each group who uses that type of social media and divide by the total of each group; then multiply: