A cyclist bikes x distance at 10 miles per hour and returns over the same path at 8 miles per hour. What is the cyclist's average rate for the round trip in miles per hour? ( please help me ! )

Answer 1

w=d/t
let x=80, so
(80+80)/(8hs+10hrs)
=8.8889 mi/hour

Answer 2

I don't know why nancy picked 80 as a value for x, since it could be almost any value.

Since the distance is the same for both rates, it the mean of 10 and 8.

(10 + 8)/2 = 9