document.write( "Question 508978: Flying with a tailwind a jet can fly 2520 miles in 4 hours. Flying against the same wind, it covers 1720 miles in the same amount of time. Determine the speed of the jet in calm air. \n" ); document.write( "
Algebra.Com's Answer #341215 by mananth(16946)\"\" \"About 
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Plane speed= x mph
\n" ); document.write( "Wind speed = y mph
\n" ); document.write( "with current speed= (x+y)
\n" ); document.write( "against current speed= (x-y)
\n" ); document.write( "d= 2520 with Wind
\n" ); document.write( "2520 / (x+y) = 4
\n" ); document.write( "divide by 4
\n" ); document.write( "630 / (x+y) = 1
\n" ); document.write( "(x+y) = 630 ............1
\n" ); document.write( "d= = 1720 against wind
\n" ); document.write( "1720 /(x-y)= 4
\n" ); document.write( "divide by 4
\n" ); document.write( "430 /(x-y) = 1
\n" ); document.write( " x - y = 430 .............2
\n" ); document.write( "add up (1) & (2)
\n" ); document.write( "2 x = 1060
\n" ); document.write( "/ 2
\n" ); document.write( "x= 530 mph speed of Plane
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "we get y= 100 mph Wind speed\r
\n" ); document.write( "\n" ); document.write( "m.ananth@hotmail.ca
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