Two youngsters were running as hard as they could. They averaged 6 miles per hour, and then had to rest. On the way back, they averaged only 4 miles per hour for the same distance. Not counting resting time, what was their average speed?
REVEAL THE ANSWER
The correct answer is 4.8, not 5, miles per hour. The answer is obtained by dividing the distance covered by the time elapsed, and any distance will do. Take a 12-mile run, for instance. That will take them two hours out and three hours back. It, therefore, took them five hours to travel 24 miles.