Asked by Anonymous
you go up a hill at 10 miles per hour and down the hill at 30 miles per hour what is the average speed and it's not 20 miles per hour
Answers
Answered by
Reiny
time to go up hill = d/10
time to go down = d/30
total time = d/10 + d/30 = 4d/30
avg speed = total distance / total time
= 2d/(4d/30)
= 2d(30/4d)
= 60/4 = 15 mph
time to go down = d/30
total time = d/10 + d/30 = 4d/30
avg speed = total distance / total time
= 2d/(4d/30)
= 2d(30/4d)
= 60/4 = 15 mph