document.write( "Question 1002245: Hi,\r
\n" ); document.write( "\n" ); document.write( "I would like to just start off by saying thank you for your help.\r
\n" ); document.write( "\n" ); document.write( "My question is as follows.\r
\n" ); document.write( "\n" ); document.write( "A canoeist can paddle 20.0 Km down a certain river and back in 8.0 hrs. (40.0 Km round trip). She can also paddle 5.0 km down river in the same time as she paddles 3.0 km up river. Find her rate in still water, and find the rate of the current. \r
\n" ); document.write( "\n" ); document.write( "Thanks again \n" ); document.write( "

Algebra.Com's Answer #619191 by josgarithmetic(39620) $\"\"$ $\"About$

You can put this solution on YOUR website!
Look at the second part of the description first.
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document.write( "             rate     time    distance\r\n" );
document.write( "DOWN         r+c       t       5\r\n" );
document.write( "UP           r-c       t       3\r\n" );
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\n" ); document.write( " $\"system%28rt%2Bct=5%2Crt-ct=3%29\"$
\n" ); document.write( "Really want a relationship between r and c.
\n" ); document.write( " $\"t=5%2F%28r%2Bc%29=3%2F%28r-c%29\"$
\n" ); document.write( " $\"5%28r-c%29=3%28r%2Bc%29\"$
\n" ); document.write( " $\"5r-5c=3r%2B3c\"$
\n" ); document.write( " $\"2r-5c=3c\"$
\n" ); document.write( " $\"2r=8c\"$
\n" ); document.write( " $\"highlight_green%28r=4c%29\"$ or $\"highlight_green%28c=r%2F4%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Now analyze the first part of the description.
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document.write( "DOWN       r+c         ()         20\r\n" );
document.write( "UP         r-c         ()         20\r\n" );
document.write( "TOTAL                  8          40\r\n" );
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\n" ); document.write( "We can begin filling the two missing time cells.
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\r\n" );
document.write( "DOWN       r+c         20/(r+c)         20\r\n" );
document.write( "UP         r-c         20/(r-c)         20\r\n" );
document.write( "TOTAL                  8               40\r\n" );
document.write( "

\n" ); document.write( "The time-sum equation should be obvious:
\n" ); document.write( " $\"20%2F%28r%2Bc%29%2B20%2F%28r-c%29=8\"$ .
\n" ); document.write( "Try simplifying this equation before substituting either for r or for c.\r
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\n" ); document.write( "\n" ); document.write( "I have not finished this but you should be able to. \n" ); document.write( "

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