PSAT Math Grid-Ins Question 40: Answer and Explanation

Question: 40

The graph above shows the amount of time, in hours, that Robert spends jogging in each month through a particular year. The information for the month of December is not included in the graph.

In June, Robert ran at a pace of 5 miles per hour at the beginning of the month before he increased in pace to 6 miles per hour toward the end of the month. If he spent 70% of this jogging time at the slower pace, and the rest at the faster pace, what is the total distance, in miles that Robert jogged during the month of June?

Correct Answer: 636

Explanation:

636

The question asks for the total distance jogged during June. According to the graph, Robert spent 120 hours jogging. The question says that Robert spent 70% his jogging time at the slower pace, which was 5 miles per hour. Therefore, he spent hours at 5 miles per hour. To find the distance, multiply the rate by the time to get 84 × 5 = 420 miles. He spent the rest of the time at the faster pace. The remaining time is 120 - 84 = 36, so he spent 36 hours at 6 miles per hour for a distance of 36 × 6 = 216. Thus, the total distance traveled for the month is 420 + 216 = 636 miles. The correct answer is 636.