document.write( "Question 965150: An airplane takes 3.6 hours to fly 1800 miles against the wind. It only takes the plane 3 hours to return 1800 miles with the wind. Assuming that the plane flies at a constant speed, how long will it take it to fly 3300 miles when there is no wind? \n" ); document.write( "

Algebra.Com's Answer #589911 by MathTherapy(10551) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "An airplane takes 3.6 hours to fly 1800 miles against the wind. It only takes the plane 3 hours to return 1800 miles with the wind. Assuming that the plane flies at a constant speed, how long will it take it to fly 3300 miles when there is no wind?
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Let speed in calm air be S, and wind, W
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document.write( "To travel 1,800 miles in 3.6 hours against the wind, total speed = , or 500 mph
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document.write( "We then have: S - W = 500 ------- eq (i)\r
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document.write( "To travel 1,800 miles in 3 hours with the wind, total speed = , or 600 mph
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document.write( "We then have: S + W = 600 ------- eq (ii)
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document.write( "2S = 1,100 ------- Adding eqs (ii) & (i)
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document.write( "S, or speed in still air = , or 550 mph\r
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document.write( "Time taken to travel 3,300 miles in calm air = , or  hours \n" );
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