document.write( "Question 1007654: A person rowed their boat downstream for 100 miles and they took 2 hours. Returning upstream, the trip took 2 hours and 40 minutes.\r
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document.write( "What is the speed of the water?
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Algebra.Com's Answer #623538 by mananth(16949) You can put this solution on YOUR website! \n" ); document.write( "Boat speed speed =x mph \n" ); document.write( "stream speed =y mph \n" ); document.write( "against stream 2 2/3 hours \n" ); document.write( "with stream 2 hours \n" ); document.write( " \n" ); document.write( "Distance with stream 100 miles distance against stream 100 \n" ); document.write( "t=d/r against stream (x-y) \n" ); document.write( "100 / ( x - y )= 2 2/3 \n" ); document.write( " \n" ); document.write( "2 2/3 x - -2 2/3 y = 100 ....................1 \n" ); document.write( "with stream (x+y) \n" ); document.write( "100 / ( x + y )= 2 \n" ); document.write( "2 ( x + y ) = 100 \n" ); document.write( "2 x + 2 y = 100 ...............2 \n" ); document.write( "Multiply (1) by 2 \n" ); document.write( "Multiply (2) by 2 2/3 \n" ); document.write( "we get 2 \n" ); document.write( "5 1/3 x + -5 1/3 y = 200 \n" ); document.write( "5 1/3 x + 5 1/3 y = 267 \n" ); document.write( "10 2/3 x = 467 \n" ); document.write( "/ 10 2/3 \n" ); document.write( "x = 43 3/4 mph \n" ); document.write( " \n" ); document.write( "plug value of x in (1) y \n" ); document.write( "2 2/3 x -2 2/3 y = 100 \n" ); document.write( "116 2/3 -2 2/3 -116 2/3 = 100 \n" ); document.write( "-2 2/3 y = 100 \n" ); document.write( "-2 2/3 y = -16 2/3 mph \n" ); document.write( " y = 6 1/4 \n" ); document.write( "Boat speed 43 3/4 mph \n" ); document.write( "stream 6 1/4 mph \n" ); document.write( " \n" ); document.write( "CHECK \n" ); document.write( "x+y= 50 \n" ); document.write( "X-y= 37 1/2 \n" ); document.write( "100 / ( 43 3/4 + 6 1/4 )= 2 \n" ); document.write( "100 / ( 43 3/4 )- 6 1/4 = 2 2/3 \n" ); document.write( " \n" ); document.write( " |