Question 962530
Susan rode the trolley to the park at 20 mph and jogged back at 8 mph. If the round trip took 7 hours, how far is it to the park ? The answer I got was 40 miles, but I would love to be sure. 
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To park DATA:
rate = 20 mph ; distance = x miles ; time = d/r = x/20 hrs
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From park DATA:
rate = 8 mph ; distance = x miles ; time = d/r = x/8 hrs
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Equation:
time + time = 7 hrs
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x/20 + x/8 = 7 hrs
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8x + 20x = 7*20*8
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28x = 1200
x = 40 miles :: (You are correct)
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Cheers,
Stan H.
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