document.write( "Question 1132762: A boat travelled 32 miles downstream and then it travelled back. The trip downstream took 4 hours. The trip back took 8 hours. What is the speed of the boat in still water? What is the speed of the current.
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Algebra.Com's Answer #749883 by ankor@dixie-net.com(22740)\"\" \"About 
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A boat travelled 32 miles downstream and then it travelled back.
\n" ); document.write( " The trip downstream took 4 hours. The trip back took 8 hours.
\n" ); document.write( " What is the speed of the boat in still water?
\n" ); document.write( " What is the speed of the current.
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\n" ); document.write( "let s = speed of boat in still water
\n" ); document.write( "let c = rate of the current
\n" ); document.write( "then, in relation to the earth:
\n" ); document.write( "(s+c) = speed downstream
\n" ); document.write( "and
\n" ); document.write( "(s-c) = speed upstream
\n" ); document.write( ":
\n" ); document.write( "Write a distance equation for each way
\n" ); document.write( "4(s+c) = 32
\n" ); document.write( "8(s-c) = 32
\n" ); document.write( "Simplify, divide the 1st equation by 4 and the 2nd equation by 8
\n" ); document.write( "s + c = 8
\n" ); document.write( "s - c = 4
\n" ); document.write( "----------addition eliminates c, find s
\n" ); document.write( "2s = 12
\n" ); document.write( "s = 6 mph is the speed in still water
\n" ); document.write( "and
\n" ); document.write( "6 + c = 8
\n" ); document.write( "c = 2 mph is the rate of the current
\n" ); document.write( ":
\n" ); document.write( "Check this by finding the travel times with these values
\n" ); document.write( "32/(6+2) = 4
\n" ); document.write( "32/(6-2) = 8\r
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