Question

Xavier drove from his house to the country in 3 hours. Driving at a speed of 12 mph less than on the trip out, he spent 4 hours on the return trip. What was his average rate on the return trip?

Answer 1

36 mph

Explanation:

Let s represent the return trip speed. Then s+12 will be the speed on the trip out. The distance is presumed the same on both trips. We can use ...

speed · time = distance

(3)(s +12) = 4(s)

36 = s . . . . . . . . . . . subtract 3s and simplify

The return trip speed was 36 miles per hour.