document.write( "Question 414612: John paddled for 4hrs with a 4 km/hr current to reach a campsite. The return trip against the same current took 10hrs. Find the speed of John's canoe in still water.\r
\n" ); document.write( "\n" ); document.write( "I tried d=(r-4)4 and d=(r+4)10
\n" ); document.write( "10r+40 = 4r-16
\n" ); document.write( "6r+40 = -16
\n" ); document.write( "6r = -56
\n" ); document.write( "r=-9.333
\n" ); document.write( "Doesn't seem right? a - in still water? \n" ); document.write( "
Algebra.Com's Answer #290827 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
John paddled for 4hrs with a 4 km/hr current to reach a campsite. The return trip against the same current took 10hrs. Find the speed of John's canoe in still water.
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\n" ); document.write( "With Current DATA:
\n" ); document.write( "time = 4 hrs ; rate = c+4 km/h ; distance = t*r = 4(c+4) = 4c+16 km
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\n" ); document.write( "Against Current DATA:
\n" ); document.write( "time = 10 hrs ; rate = c-4 km/h ; distance = t*r = 10(c-4) = 10c-40 km
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\n" ); document.write( "Equation:
\n" ); document.write( "distance with = distance against
\n" ); document.write( "4c+16 = 10c-40
\n" ); document.write( "6c = 56
\n" ); document.write( "c = 9 1/3 km/h (speed of the canoe in still water)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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