document.write( "Question 370080: A plane flies 450 miles with the wind and 350 miles against the wind in the same length of time. If the speed of the wind is 28 mph, what is the speed of the plane in still air? \n" ); document.write( "

Algebra.Com's Answer #263735 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "d = rt   t =d/r  
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document.write( "Times are the same.
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document.write( "Let r represent the speed in still air
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document.write( "cross multiply to solve
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document.write( "450(r-28) = 350(r+28)
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document.write( "450r - 450*28 = 350r + 350*28
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document.write( "100r = 800*28
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document.write( "r = 8*28 = 224mph is the speed of the plane in still air
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document.write( "checking our answer
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document.write( "450/252 = 350/196 = 1.79 hr
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