document.write( "Question 481107: A motorboat can travel 24 miles downstream in 2 hours. It requires 3 hours to make the return trip. Find the rate of the boat in still water and the rate of the stream. \n" ); document.write( "

Algebra.Com's Answer #329455 by mananth(16946) $\"\"$ $\"About$

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boat speed =x mph
\n" ); document.write( "current speed =y mph
\n" ); document.write( "against current x-y 3.00 hours
\n" ); document.write( "with current x+y 2.00 hours
\n" ); document.write( "
\n" ); document.write( "Distance = same= 24 miles
\n" ); document.write( "t=d/r
\n" ); document.write( "24 / ( x - y )= 3.00
\n" ); document.write( "3 ( x - y ) = 24.00
\n" ); document.write( "3 x -3 y = 24 ....................1
\n" ); document.write( "24 / ( x + y )= 2.00
\n" ); document.write( "2.00 ( x + y ) = 24
\n" ); document.write( "2.00 x + 2.00 y = 24 ...............2
\n" ); document.write( "Multiply (1) by 2.00
\n" ); document.write( "Multiply (2) by 3.00
\n" ); document.write( "we get
\n" ); document.write( "6 x + -6 y = 48
\n" ); document.write( "6 x + 6 y = 72
\n" ); document.write( "12 x = 120
\n" ); document.write( "/ 12
\n" ); document.write( "x = 10 mph
\n" ); document.write( "
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "3 x -3 y = 24
\n" ); document.write( "30 -3 y = 24
\n" ); document.write( "-3 y = 24 -30
\n" ); document.write( "-3 y = -6
\n" ); document.write( " y = 2 mph
\n" ); document.write( "m.ananth@hotmail.ca \n" ); document.write( "

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