document.write( "Question 876468: Lance Armstrong can ride 162 miles on flat ground in 6 hours with a good breeze at his back. it takes him 10 hours to go 90 miles with the same breeze working against him. How fast is lance going on a bike and how fast is the wind speed? \n" ); document.write( "
Algebra.Com's Answer #528791 by mananth(16946)\"\" \"About 
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bike speed =x mph
\n" ); document.write( "wind speed given speed =y mph
\n" ); document.write( "against wind speed given 10 hours
\n" ); document.write( "with wind speed given 6 hours
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\n" ); document.write( "Distance against 90 miles distance with 162 miles
\n" ); document.write( "t=d/r against wind speed given -
\n" ); document.write( "90.00 / ( x - y )= 10.00
\n" ); document.write( "10.00 ( x - y ) = 6.00
\n" ); document.write( "10.00 x - 10.00 y = 90.00 ....................1
\n" ); document.write( "
\n" ); document.write( "162.00 / ( x + y )= 6.00
\n" ); document.write( "6.00 ( x + y ) = 162.00
\n" ); document.write( "6.00 x + 6.00 y = 162.00 ...............2
\n" ); document.write( "Multiply (1) by 3.00
\n" ); document.write( "Multiply (2) by 5.00
\n" ); document.write( "we get
\n" ); document.write( "30.00 x + -30.00 y = 270.00
\n" ); document.write( "30.00 x + 30.00 y = 810.00
\n" ); document.write( "60.00 x = 1080.00
\n" ); document.write( "/ 60.00
\n" ); document.write( "x = 18.00 mph
\n" ); document.write( "
\n" ); document.write( "plug value of x in (1) y
\n" ); document.write( "10.00 x -10.00 y = 90.00
\n" ); document.write( "180.00 -10.00 -180.00 = 90.00
\n" ); document.write( "-10.00 y = 90.00
\n" ); document.write( "-10.00 y = -90.00 mph
\n" ); document.write( " y = 9.00
\n" ); document.write( "bike speed 18.00 mph
\n" ); document.write( "wind speed given speed 9.00 mph
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\n" ); document.write( "m.ananth@hotmail.ca
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