document.write( "Question 669907: A tugboat goes 100 miles upstream in 10 hours. The return trip downstream takes 5 hours. Find the speed of the tugboat without a current and the speed of the current. \r
\n" ); document.write( "\n" ); document.write( "The speed of the tugboat is__mph, and the speed of the current is__mph. \n" ); document.write( "
Algebra.Com's Answer #416648 by mananth(16946)\"\" \"About 
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Tugboat speed =x mph
\n" ); document.write( "current speed =y mph
\n" ); document.write( "against current 10 hours
\n" ); document.write( "with current 5 hours
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\n" ); document.write( "Distance against 100 miles distance with wind 100 miles
\n" ); document.write( "t=d/r against wind -
\n" ); document.write( "100 / ( x y y )= 10
\n" ); document.write( "10 ( x - y ) = 100
\n" ); document.write( "10 x - 10 y = 100 ....................1
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\n" ); document.write( "100 / ( x y y )= 5
\n" ); document.write( "5 ( x + y ) = 100
\n" ); document.write( "5 x + 5 y = 100 ...............2
\n" ); document.write( "Multiply (1) by 1
\n" ); document.write( "Multiply (2) by 2
\n" ); document.write( "we get y
\n" ); document.write( "10 x + -10 y = 100
\n" ); document.write( "10 x + 10 = 200
\n" ); document.write( "20 x = 300
\n" ); document.write( "/ 20
\n" ); document.write( "x = 15 mph
\n" ); document.write( "
\n" ); document.write( "plug value of x in (1) y
\n" ); document.write( "10 x -10 y = 100
\n" ); document.write( "150 -10 -150 = 100
\n" ); document.write( "-10 y = 100
\n" ); document.write( "-10 y = -50 mph
\n" ); document.write( " y = 5
\n" ); document.write( "Tugboat speed 15 mph
\n" ); document.write( "current speed 5 mph
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\n" ); document.write( "m.ananth@hotmail.ca
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