document.write( "Question 933082: Mr. paddle took his boat 80 miles down a river and back.The trip downsteam took 4hrs while back took 8hrs.find the speed of the boat in still water and the speed of the current?
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Algebra.Com's Answer #566649 by ptfile(81) $\"\"$ $\"About$

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Let 80 miles = the distance Mr. Paddle traveled
\n" ); document.write( " 4hrs = the duration of the boat traveled on downstream
\n" ); document.write( " 8hrs = the duration of the boat traveled on upstream\r
\n" ); document.write( "\n" ); document.write( "Mr. paddle took his boat 80 miles down a river and back. The trip downstream took 4hrs while back took 8hrs.\r
\n" ); document.write( "\n" ); document.write( "Distance = (rate)(time)
\n" ); document.write( "rate = Distance/time\r
\n" ); document.write( "\n" ); document.write( " 80 = (x+y)4
\n" ); document.write( " 10 = x+y
\n" ); document.write( " 80 = (x-y)8
\n" ); document.write( " 20 = x-y\r
\n" ); document.write( "\n" ); document.write( "x+y = 20
\n" ); document.write( "x-y = 10
\n" ); document.write( " 2x = 30
\n" ); document.write( " x = 15\r
\n" ); document.write( "\n" ); document.write( "Substitute x with 15
\n" ); document.write( "15+y = 20
\n" ); document.write( " y = 5
\n" ); document.write( "15-y = 10
\n" ); document.write( " y = 5\r
\n" ); document.write( "\n" ); document.write( "The boat's speed is 15kph while the current's speed is 5kph.\r
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