document.write( "Question 292873: A boat traveled 336 miles downstream and back. The trip downstream took 12 hours. The trip back
\n" ); document.write( "took 14 hours. What is the speed of the boat in still water? What is the speed of the current?
\n" ); document.write( "12) \n" ); document.write( "
Algebra.Com's Answer #211511 by ankor@dixie-net.com(22740)\"\" \"About 
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A boat traveled 336 miles downstream and back.
\n" ); document.write( " The trip downstream took 12 hours.
\n" ); document.write( " The trip back took 14 hours.
\n" ); document.write( " What is the speed of the boat in still water?
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\n" ); document.write( "Let s = boat speed in still water
\n" ); document.write( "Let c = speed of the current
\n" ); document.write( "then
\n" ); document.write( "(s-c) = effective speed upstream
\n" ); document.write( "(s+c) = effective speed downstream
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\n" ); document.write( "Write two distance equations; dist = time * speed
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\n" ); document.write( "14(s-c) = 336
\n" ); document.write( "12(s+c) = 336
\n" ); document.write( ":
\n" ); document.write( "Simplify; divide the 1st eq by 14, and the 2nd eq by 12, results
\n" ); document.write( "s - c = 24
\n" ); document.write( "s + c = 28
\n" ); document.write( "------------Addition eliminates c, find s
\n" ); document.write( "2s = 52
\n" ); document.write( "s = \"52%2F2\"
\n" ); document.write( "s = 26 mph in still water
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\n" ); document.write( "What is the speed of the current? we know: s + c = 28, replace s:
\n" ); document.write( "26 + c = 28
\n" ); document.write( "c = 28 - 26
\n" ); document.write( "c = 2 mph current \n" ); document.write( "
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