SOLUTION: A man drives a car a distance of 200 km at an average speed of 44 km/h. What must be his average speed for the next 220 km if he is to cover the total distance in 9 hours?

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Question 736247: A man drives a car a distance of 200 km at an average speed of 44 km/h. What must be his average speed for the next 220 km if he is to cover the total distance in 9 hours?
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
A man drives a car a distance of 200 km at an average speed of 44 km/h. What must be his average speed for the next 220 km if he is to cover the total distance in 9 hours?
He wants to have gone the entire 420 miles in 9 hours. 

He has driven 200 km at 44 km/h.

Since TIME=DISTANCE%2FRATE, he has spent 200%2F44 or 50%2F11 or 4%266%2F11 hours.

So he has 220 miles to go, and he has 9-4%266%2F11 or 49%2F11 or 4%265%2F11 hours left. So since RATE=DISTANCE%2FTIME,

                  220%2F%2849%2F11%29 = 220×expr%2811%2F49%29 = 2420%2F49 or 49%2619%2F49 km/hr.

                  He must go 49%2619%2F49 km/hr.

Edwin