SOLUTION: At a given hour, two cars leave a city in the same direction. One travels at 60 mph, and the other travels at 75 mph. In how many hours will the cars be 90 miles apart?

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Question 77309This question is from textbook introductory to algebra
: At a given hour, two cars leave a city in the same direction. One travels at 60 mph, and the other travels at 75 mph. In how many hours will the cars be 90 miles apart? This question is from textbook introductory to algebra

Found 2 solutions by checkley75, stanbon:
Answer by checkley75(3666) (Show Source):
You can put this solution on YOUR website!
75x-60x=90
15x=90
x=90/15
x=6 hours after they depart they'll be 90 miles apart.
proof
75*6-60*6=90
450-360=90
90=90

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
At a given hour, two cars leave a city in the same direction. One travels at 60 mph, and the other travels at 75 mph. In how many hours will the cars be 90 miles apart?
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1st car:
rate = 60 mph ; time=x hrs. ; distance 60x miles
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2nd car:
rate = 75 mph ; time = x hrs. ; distance = 75x miles
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EQUATION:
2nd car distance - 1st car distance = 90 miles
75x - 60x = 90
15x = 90
x=6 hrs (time after they will be 90 miles apart)
Cheers,
Stan H.