document.write( "Question 1045968: A paddleboat can move at a speed of 6 km/h in still water. The boat is paddled
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Algebra.Com's Answer #661473 by ikleyn(52776) $\"\"$ $\"About$

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\n" ); document.write( "A paddle-boat can move at a speed of 6 km/h in still water. The boat is paddled
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document.write( "Let \"u\" be the speed of the river.\r\n" );
document.write( "Then the speed of the paddle-boat floating downstream is 6 +u km/h.\r\n" );
document.write( "and  the speed of the paddle-boat floating upstream   is 6 -u km/h.\r\n" );
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document.write( "Time it spends for floating 16 km downstream is  hours.\r\n" );
document.write( "Time it spends for floating  8 km upstream   is  hours.\r\n" );
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document.write( "These times are equal, so you have an equation\r\n" );
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document.write( " = .\r\n" );
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document.write( "To solve it, multiply both sides by (6+u)*(6-u). You will get\r\n" );
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document.write( "16(6-u) = 8(6+u),  or\r\n" );
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document.write( "96 - 16u = 48 + 8u,  or\r\n" );
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document.write( "48 = 24u.\r\n" );
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document.write( "Hence, u=2.\r\n" );
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document.write( "Answer.  the speed of the river is 2 km/h.\r\n" );
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\n" ); document.write( "\n" ); document.write( "For more similar solved problems of this type see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Wind and Current problems \r
\n" ); document.write( "\n" ); document.write( "    - More problems on upstream and downstream round trips \r
\n" ); document.write( "\n" ); document.write( "    - Selected problems from the archive on the boat floating Upstream and Downstream \r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
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