document.write( "Question 915210: A boat crew rowed 13.5 miles with the current in 1.5 hours. The return trip against the current covered the same distance but took 4.5 hours. Find crews rate in still water and rate of current. \n" ); document.write( "
Algebra.Com's Answer #555502 by mananth(16946)\"\" \"About 
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Boat speed speed =x mph
\n" ); document.write( "current speed =y mph
\n" ); document.write( "against current 4.5 hours
\n" ); document.write( "with current 1.5 hours
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\n" ); document.write( "Distance against 13.5 miles distance with 13.5 miles
\n" ); document.write( "t=d/r against current -
\n" ); document.write( "13.50 / ( x - y )= 4.50
\n" ); document.write( "4.50 ( x - y ) = 1.50
\n" ); document.write( "4.50 x - 4.50 y = 13.50 ....................1
\n" ); document.write( "
\n" ); document.write( "13.50 / ( x + y )= 1.50
\n" ); document.write( "1.50 ( x + y ) = 13.50
\n" ); document.write( "1.50 x + 1.50 y = 13.50 ...............2
\n" ); document.write( "Multiply (1) by 1.50
\n" ); document.write( "Multiply (2) by 4.50
\n" ); document.write( "we get
\n" ); document.write( "6.75 x + -6.75 y = 20.25
\n" ); document.write( "6.75 x + 6.75 y = 60.75
\n" ); document.write( "13.50 x = 81.00
\n" ); document.write( "/ 13.50
\n" ); document.write( "x = 6.00 mph
\n" ); document.write( "
\n" ); document.write( "plug value of x in (1) y
\n" ); document.write( "4.50 x -4.50 y = 13.50
\n" ); document.write( "27.00 -4.50 -27.00 = 13.50
\n" ); document.write( "-4.50 y = 13.50
\n" ); document.write( "-4.50 y = -13.50 mph
\n" ); document.write( " y = 3.00
\n" ); document.write( "Boat speed speed 6.00 mph
\n" ); document.write( "current speed 3.00 mph
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\n" ); document.write( "m.ananth@hotmail.ca
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