PSAT Math Multiple-Choice Question 562: Answer and Explanation

Question: 562

A subway map is drawn to scale so that 1 inch on the map corresponds to 2 miles of actual distance on the track. The subway train travels at a constant average rate of 30 miles per hour. How many minutes will a journey on the subway take if the track distance as portrayed on the map is 3 inches?

• A. 6
• B. 9
• C. 12
• D. 18

Correct Answer: C

Explanation:

(C) Since 1 inch on the map corresponds to 2 miles of actual distance, double the 3 inches shown on the map to determine that the subway has traveled 6 actual miles. Since the subway is traveling at 30 miles per hour, solve for the number of hours the subway has traveled:

Distance = Rate × Time

6 = 30 × Time

Time = hours

Then multiply by 60 minutes to determine how many minutes the train takes to travel 6 miles:

× 60 = 12 minutes