SOLUTION: A six-passenger plane cruises at 180mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the win
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-> SOLUTION: A six-passenger plane cruises at 180mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the win
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Question 90057: A six-passenger plane cruises at 180mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the wind speed? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! six-passenger plane cruises at 180mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the wind speed?
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Let wind speed be "x mph"
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With the wind DATA:
Distance = 7 miles ; Rate = 180+x mph ; Time = d/r = 7/(180+x) hrs
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Against the wind DATA:
Distance = 5 miles ; Rate = 180-x mph ; Time = d/r = 5/(180-x) hrs
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EQUATION:
time with wind = time against wind
7/(180+x) = 5/(180-x)
7*180-7x = 5*180+5x
12x = 2*180
x = 30 (wind speed)
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Cheers,
Stan H.
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