document.write( "Question 969896: A boat goes downstream 72 miles in 3 hours, and travels upstream 60 miles in 6 hours. What is the rate of the river, and what is the boat in still water? \n" ); document.write( "

Algebra.Com's Answer #593037 by lwsshak3(11628) $\"\"$ $\"About$

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A boat goes downstream 72 miles in 3 hours, and travels upstream 60 miles in 6 hours. What is the rate of the river, and what is the boat in still water?
\n" ); document.write( "***
\n" ); document.write( "let x=rate of boat in still water
\n" ); document.write( "let c= rate of the river
\n" ); document.write( "x+c=rate of boat downstream
\n" ); document.write( "x-c=rate of boat upstream
\n" ); document.write( "travel time*rate=distance
\n" ); document.write( "..
\n" ); document.write( "3(x+c)=72
\n" ); document.write( "6(x-c)=60
\n" ); document.write( "..
\n" ); document.write( "3x+3c=72
\n" ); document.write( "6x-6c=60
\n" ); document.write( "..
\n" ); document.write( "6x+6c=144
\n" ); document.write( "6x-6c=60
\n" ); document.write( "add
\n" ); document.write( "12x=204
\n" ); document.write( "x=17
\n" ); document.write( "..
\n" ); document.write( "subtract:
\n" ); document.write( "12c=84
\n" ); document.write( "c=7
\n" ); document.write( "rate of boat in still water=17 mph
\n" ); document.write( "rate of the river current=7 mph
\n" ); document.write( " \n" ); document.write( "

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