document.write( "Question 998700: Adam and Natasha row their canoe 21 miles downstream in 3 hours. After a picnic, they row their canoe back upstream. After 4 hours of rowing, they only travel 20 miles. Assuming that Adam and Natasha canoe at a constant rate, and that the river's current is constant, find the speed at which Adam and Natasha can row in still water. \n" ); document.write( "

Algebra.Com's Answer #616468 by josgarithmetic(39620) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "               rate         time          distance\r\n" );
document.write( "DOWN           r+c           3              21\r\n" );
document.write( "UPST           r-c           4              20\r\n" );
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\n" ); document.write( "\n" ); document.write( " $\"system%28r%2Bc=7%2Cr-c=5%29\"$
\n" ); document.write( "Two linear equation in two unknown variables. \n" ); document.write( "

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