document.write( "Question 601587: If a boat goes downstream 72 miles in 3 hours and upstream 60 miles in 6 hours, the rate of the river and the rate of the boat in still water respectively are ________? \n" ); document.write( "
Algebra.Com's Answer #379884 by lwsshak3(11628)\"\" \"About 
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If a boat goes downstream 72 miles in 3 hours and upstream 60 miles in 6 hours, the rate of the river and the rate of the boat in still water respectively are:
\n" ); document.write( "**
\n" ); document.write( "let x=rate of speed of boat in still water
\n" ); document.write( "let c=rate of speed of current
\n" ); document.write( "net speed of boat downstream=x+c
\n" ); document.write( "net speed of boat upstream=x-c
\n" ); document.write( "distance = travel time*speed
\n" ); document.write( "..
\n" ); document.write( "3(x+c)=72
\n" ); document.write( "6(x-c)=72
\n" ); document.write( "..
\n" ); document.write( "3x+3c=72
\n" ); document.write( "6x-6c=72
\n" ); document.write( "..
\n" ); document.write( "6x+6c=144 (mult.by 2)
\n" ); document.write( "6x-6c=72
\n" ); document.write( "add
\n" ); document.write( "12x=216
\n" ); document.write( "x=18
\n" ); document.write( "6c=144-6x=36
\n" ); document.write( "c=6
\n" ); document.write( "ans:
\n" ); document.write( "rate of speed of boat in still water=18 mph
\n" ); document.write( "rate of speed of current=6 mph \n" ); document.write( "
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