Question

A man walks 6 miles at 4 miles per hour. At what speed would he need to travel during the next 2 1/2 hours to have an average speed of 6 miles per hour during the complete trip?

Answer 1

In order to have an average speed of 6 miles per hour over the entirety of the trip, the man would need to travel 15 miles in the next 2 1/2 hours. This means that he would need to travel at a speed of 6 miles per hour for the remainder of the trip.