document.write( "Question 822502: a plane can fly 1120 km in 80 min with the wind. Flying against the same wind, the plane travels the same distance in 84 min. Find the speed of the wind and the speed of the plane in still air. \n" ); document.write( "
Algebra.Com's Answer #494888 by stanbon(75887)\"\" \"About 
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a plane can fly 1120 km in 80 min with the wind. Flying against the same wind, the plane travels the same distance in 84 min. Find the speed of the wind and the speed of the plane in still air.
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\n" ); document.write( "rate with wind:: 1120 km/(4/3)hr = 840 km/hr
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\n" ); document.write( "rate against with: 1120/(84/60) = 800 km/hr
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\n" ); document.write( "Equation:
\n" ); document.write( "With wind:: p + w = 840
\n" ); document.write( "Against wind:: p - w + 800
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\n" ); document.write( "2p = 1640
\n" ); document.write( "plane speed = 820 km/hr
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\n" ); document.write( "Solve for \"w\":
\n" ); document.write( "p + w = 840
\n" ); document.write( "820 + w = 840
\n" ); document.write( "w = 20 km/hr
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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