document.write( "Question 633053: A tugboat goes 120 miles upstream in 10 hours. The return trip downstream takes 5 hours. Find the speed of the tugboat without current and the speed of the current. \n" ); document.write( "
Algebra.Com's Answer #398629 by mananth(16946)\"\" \"About 
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Boat speed =x mph
\n" ); document.write( "current speed =y mph
\n" ); document.write( "againstcurrent x-y 10 hours
\n" ); document.write( "with current x+y 5 hours
\n" ); document.write( "
\n" ); document.write( "Distance = 120 miles distance= 120
\n" ); document.write( "t=d/r against current
\n" ); document.write( "120.00 / ( x - y )= 10.00
\n" ); document.write( "
\n" ); document.write( "10.00 x - -10.00 y = 120.00 ....................1
\n" ); document.write( "downstream
\n" ); document.write( "120.00 / ( x + y )= 5.00
\n" ); document.write( "5.00 ( x + y ) = 120.00
\n" ); document.write( "5.00 x + 5.00 y = 120.00 ...............2
\n" ); document.write( "Multiply (1) by 1.00
\n" ); document.write( "Multiply (2) by 2.00
\n" ); document.write( "we get
\n" ); document.write( "10.00 x + -10.00 y = 120.00
\n" ); document.write( "10.00 x + 10.00 y = 240.00
\n" ); document.write( "20.00 x = 360.00
\n" ); document.write( "/ 20.00
\n" ); document.write( "x = 18 mph
\n" ); document.write( "
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "10 x -10 y = 120
\n" ); document.write( "180 -10 y = 120
\n" ); document.write( "-10 y = 120 -180
\n" ); document.write( "-10 y = -60
\n" ); document.write( " y = 6 mph
\n" ); document.write( " Boat 18 mph
\n" ); document.write( " current 6 mph
\n" ); document.write( "m.ananth@hotmail.ca \n" ); document.write( "
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