jmc

Question

Joann rode her bike at an average speed of 12 miles per hour for three and a half hours. If her friend, Fran, rides for 3 hours, at what average speed, in miles per hour, would she have to ride her bike to travel the same distance that Joann traveled?

Accepted Answer

In 312 hours, Joann covers (312 hours)(12 mph)=42 miles. If Fran's average speed in miles per hour is s, then Fran covers 3s miles in 3 hours. Solving 3s=42 we find s=14 miles per hour.