document.write( "Question 428944: Flying from Tokyo to London is approximately 6175 miles. On the way to London from Tokyo(against the wind) the flight took 13 hours. The return flight (with the wind) took 9.88 hours. Find out the speed of the plane in still air and the speed of the wind current \n" ); document.write( "

Algebra.Com's Answer #298027 by mananth(16946) $\"\"$ $\"About$

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against wind 13.00 hours
\n" ); document.write( "with wind 9.88 hours
\n" ); document.write( "
\n" ); document.write( "Distance = same= 6175
\n" ); document.write( "plane speed =x
\n" ); document.write( "wind speed =y
\n" ); document.write( "t=d/r
\n" ); document.write( "6175/(x-y)=13.00
\n" ); document.write( "13(x-y)=6,175.00
\n" ); document.write( "13x-13y =6175 ....................1
\n" ); document.write( "6175/(x +y)=9.88
\n" ); document.write( "9.88(x+y)=6175
\n" ); document.write( "9.88x+9.88y=6175...............2
\n" ); document.write( "Multiply (1) by 9.88
\n" ); document.write( "Multiply (2) by 13.00
\n" ); document.write( "we get
\n" ); document.write( "128.44x -128.44y=61009
\n" ); document.write( "128.44x +128.44y=80275
\n" ); document.write( "256.88x=141284
\n" ); document.write( "/256.88
\n" ); document.write( "x=550mph plane speed
\n" ); document.write( "
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "13x-13y =6175
\n" ); document.write( "7150-13y=6175
\n" ); document.write( "-13y=6175-7150
\n" ); document.write( "-13y=-975
\n" ); document.write( "y=75mph wind speed
\n" ); document.write( " \n" ); document.write( "

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