Question 944043: "a plane travels 8400 km against the wind in 7 hours. with the wind, the plane makes the return trip in 6 hours. find the speed of the plane in still air and the speed of the wind."
i know the variables are 8400 km, 7 hours and 6 hours, but im really confused on how to set up the equation for this problem.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! a plane travels 8400 km against the wind in 7 hours. with the wind, the plane makes the return trip in 6 hours. find the speed of the plane in still air and the speed of the wind."
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Against::
dist = 8400 ; time = 7 hrs ; time = 8400/7 = 1200 mph
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With::
dist = 8400 ; time = 6 hrs ; time = 8400/6 = 1400 mp
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Equations:
Against:: p - w = 1200
With:::: p + w = 1400
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Add and solve for "p"
2p = 2600
plane speed = 1300 mph (speed in still air)
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Subtract and solve for "w"
2w = 200
w = 100 mph (speed of the wind)
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Cheers,
Stan H.
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