document.write( "Question 90372: It took the pilot a hour and a half to make a flight of 240 miles when flying against the wind. If the return trip took an hour and 12 minutes, what was the speed of the wind? \n" ); document.write( "
Algebra.Com's Answer #65586 by stanbon(75887)\"\" \"About 
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It took the pilot a hour and a half to make a flight of 240 miles when flying against the wind. If the return trip took an hour and 12 minutes, what was the speed of the wind?
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\n" ); document.write( "Against the wind DATA:
\n" ); document.write( "Time = 1.5 hrs ; distance = 240 miles; rate = d/t = 240/1.5 = 160 mph
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\n" ); document.write( "With the wind DATA:
\n" ); document.write( "Time = 1.2 hrs ; distance = 240; rate = d/t = 240/1.2 = 200 mph
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\n" ); document.write( "Let speed of plane in calm air be p; Let speed of wind be w.
\n" ); document.write( "EQUATIONS:
\n" ); document.write( "p+w = 200
\n" ); document.write( "p-w = 160
\n" ); document.write( "Adding you get 2p=360
\n" ); document.write( "p = 180 (speed of plane in still air)
\n" ); document.write( "180 + w = 200
\n" ); document.write( "w = 20 (speed of the wind)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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