document.write( "Question 28492: PLEASE HELP ASAP:Flying against the jetstream, a jet travels 4240km in 8 hours. Flying with the jetstream, the plane travels 2910km in 3 hours. What is the speed of the jet in still air, and what is the speed of the jetstream?
\n" ); document.write( "Thank you so much \n" ); document.write( "
Algebra.Com's Answer #15481 by Paul(988)\"\" \"About 
You can put this solution on YOUR website!
Let the speed of the wind be y
\n" ); document.write( "Let the speed of the plane be y\r
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\n" ); document.write( "\n" ); document.write( "8x-8y=4240\r
\n" ); document.write( "\n" ); document.write( "second equation:
\n" ); document.write( "3(x+y)=2910
\n" ); document.write( "3x+3y=2910\r
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\n" ); document.write( "\n" ); document.write( "Multiply the first equation by 3 and the second equatin by 8
\n" ); document.write( "24x-24y=12720
\n" ); document.write( "24x+24y=23280
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\n" ); document.write( "48x=36000
\n" ); document.write( "x=750\r
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\n" ); document.write( "\n" ); document.write( "3(750)+3y=2910
\n" ); document.write( "3y=660
\n" ); document.write( "y=220\r
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\n" ); document.write( "\n" ); document.write( "Hence, the speed of the jetstream is 220mph and the speed of the plane is 750mph.
\n" ); document.write( "Paul.\r
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