SOLUTION: I am having major problems with this word problem:
On a round trip of 252 miles in each direction, the average rate of travel going was 7 mph more than the rate returning. Find
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On a round trip of 252 miles in each direction, the average rate of travel going was 7 mph more than the rate returning. Find
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Question 122739: I am having major problems with this word problem:
On a round trip of 252 miles in each direction, the average rate of travel going was 7 mph more than the rate returning. Find the rate for each direction if the entire trip took 21 hours. Answer by checkley71(8403) (Show Source):
You can put this solution on YOUR website! 252/(x+7)+252/x=21
[252x+252(x+7)]/x(x+7)=21
[252x+252x+1764]/(x^2+7x)=21 now cross multiply.
21x^2+147x=504x+1764
21x^2+147x-504x-1764=0
21x^2-357x-1764=0
21(x^2-17x-84)=0
21(x-21)(x+4)=0
x-21=0
x=21 return trip speed.
21+7=28 for the going speed.
proof
252/28+252/21=21
9+12=21
21=21