document.write( "Question 1168214: Hi
\n" ); document.write( "A man can row 8km per hour in still water. If it takes him 3 times as long to row upstream as to row down the river what would be the rate of current in the stream.\r
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Algebra.Com's Answer #792831 by ikleyn(52799) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "The \"time\" equation is \r\n" );
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document.write( "     = ,\r\n" );
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document.write( "where x is the unknown rate of the current;  d is the on way distance.\r\n" );
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document.write( "We can cancel the factor d in both sides.  Then we have\r\n" );
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document.write( "     = .\r\n" );
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document.write( "To solve this equation, first cross-multiply; then simplify\r\n" );
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document.write( "    8 + x = 3*(8-x)\r\n" );
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document.write( "    8 + x = 24 - 3x\r\n" );
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document.write( "    x + 3x = 24 - 8\r\n" );
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document.write( "    4x     = 16\r\n" );
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document.write( "     x     = 16/4 = 4.\r\n" );
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document.write( "ANSWER.  The rate of the current is 4 km/h.\r\n" );
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