Average Speed

Question

A boy riding his bicycle travels at 10 miles per hour for 3 hours. He stops to rest for one hour and then continues his ride. For the next hour he rides at 20 miles per hour. During his ride, what was the riders average speed for the five hour period?

Answer 1

10mph*(3 hours) + 20mph*(1 hour) = 50 miles

 

total time is 3 hours + 1 hour + 1 hour = 5 hours

 

50 miles/5 hours

 

10 mph