SOLUTION: A plane flies 420 miles with the wind and 300 miles against the wind in the same length of time. If the speed of the wind is 23 ​mph, what is the speed of the plane in still&
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Question 1056349: A plane flies 420 miles with the wind and 300 miles against the wind in the same length of time. If the speed of the wind is 23 mph, what is the speed of the plane in still air? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A plane flies 420 miles with the wind and 300 miles against the wind in the same length of time. If the speed of the wind is 23 mph, what is the speed of the plane in still air?
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With-wind DATA ::
dist = 420 miles ; rate = p+23 ; time = d/r = 420/(p+23) hrs
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Against-wind DATA:
dist = 300 miles ; rate = p-23 ; time = d/r = 300/(p-23) hrs
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Equation:
420/(p+23) = 300/(p-23)
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7/(p+23) = 5/(p-23)
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7p-161 = 5p+115
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2p = 276
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p = 138 mph (speed of the plane in still air)
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Cheers,
Stan H.
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