document.write( "Question 646016: It took a crew 6 h 24 min to row 6 km upstream and back again. If the rate of flow of the stream was 7 km/h, what was the rowing speed of the crew in still water? \n" ); document.write( "
Algebra.Com's Answer #405881 by ankor@dixie-net.com(22740)\"\" \"About 
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It took a crew 6 h 24 min to row 6 km upstream and back again.
\n" ); document.write( " If the rate of flow of the stream was 7 km/h, what was the rowing speed
\n" ); document.write( " of the crew in still water?
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\n" ); document.write( "Change 6 hrs, 24 min to hrs, 6 + 24/60 = 6.4 hrs
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\n" ); document.write( "Let s = rowing speed in still water
\n" ); document.write( "then
\n" ); document.write( "(s-7) = effective speed upstream
\n" ); document.write( "and
\n" ); document.write( "(s+7) = effective speed downstream
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\n" ); document.write( "Write time equation, time = dist/speed
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\n" ); document.write( "\"6%2F%28%28s-7%29%29\" + \"6%2F%28%28s%2B7%29%29\" = 6.4
\n" ); document.write( "multiply by (s-7)(s+7), obtain a quadratic equation and solve\r
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