SOLUTION: I am trying to solve this story problem It says Akron and Philadelphia are 400 miles apart. Brad's average speed is 10 miles per hour faster than Gails. Find Gail's average spee

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Question 35723: I am trying to solve this story problem
It says Akron and Philadelphia are 400 miles apart. Brad's average speed is 10 miles per hour faster than Gails. Find Gail's average speed, to the nearest tenth, if she travels from Akron to Philadelphia in 1.5 hours more time than Brad.

Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
Gail's speed is x
Brad's speed is 10+x
Equation:
400%2F%28x%29-400%2F%28x%2B10%29=1.5
400[(x+10)-(x)]=1.5[(x)(x+10)]
400(10)=1.5(x^2+10x)
4000=1.5x^2+15x
1.5x^2+15x-4000=0
solve that you get x=46.9
46.9+10=56.9
Hence, Gail's speed was 46.9mph and Brad's speed was 56.9mph.
Paul.