smc

Question

A car travels 120 miles from A to B at 30 miles per hour but returns the same distance at 40 miles per hour. The average speed for the round trip is closest to:

Accepted Answer

The car takes 120 miles 1 hr 30 miles =4 hr to get from A to B. Also, it takes 120 miles 1 hr 40 miles =3 hr to get from B to A. Therefore, the average speed is 240 miles 7 hr=3427 mph, which is closest to 34 mph.