word problem

Question

It takes a student 20 minutes to drive from school to work, a distance of 18 miles. At what average rate of speed does the student drive? Round your answer to one decimal place.

Answer 1

distance = rate * time

18 = rate * 20 => rate = 18/20 miles per minute .9 miles per minute

 

If you want the rate in miles per hour, convert 20 minutes to 1/3 hr and do the same calculation

18 = rate * (1/3) => rate = 54 mph