Mr. Green traveled to a city of 200 miles from his home to attend a meeting. Due to car trouble, his average speed returning was 10 mph less than his speed going. If the outbound trip was 4 hours and the return trip was 5 hours, at what rate of speed did he travel to the city.

Solution:

Going: x

Returning: x-10

So

x = 200/4

x-10 = 200/5

x = 50

So the going speed is 50 mph and returning speed is 40 mph