document.write( "Question 1055873: A boat travels 50 miles up the river in the same amount of time it takes to travel 62 miles down the same river. If the current is 3 miles per hour, what is the speed of the boat in still water? \n" ); document.write( "

Algebra.Com's Answer #671049 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "A boat travels 50 miles up the river in the same amount of time it takes to travel 62 miles down the same river.
\n" ); document.write( "If the current is 3 miles per hour, what is the speed of the boat in still water?
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document.write( "Let \"u\" be the current speed, in miles per hour.\r\n" );
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document.write( "Then your equation is\r\n" );
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document.write( " = .   (1)\r\n" );
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document.write( "The left part is the time spent to travel 50 miles up the river.\r\n" );
document.write( "The left part is the time spent to travel 50 miles up the river.\r\n" );
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document.write( "So, equation (1) is direct translation of the condition into math.\r\n" );
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document.write( "To solve (1), multiply bot sides by (u-3)*(u+3). You will get\r\n" );
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document.write( "50*(u+3) = 62*(u-3),\r\n" );
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document.write( "50u + 150 = 62u - 186,\r\n" );
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document.write( "150 + 186 = 62u - 50u,\r\n" );
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document.write( "336 = 12u,  --->  u =  = 28. \r\n" );
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document.write( "Answer.  The speed of the boat in still water is 28 mph.\r\n" );
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document.write( "Check.   Please do check on your own.\r\n" );
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\n" ); document.write( "\n" ); document.write( "You can find similar fully solved similar problems on upstream and downstream round trips with detailed solutions in 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( "Read them attentively and learn how to solve this type of problems once and for all.\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
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the section \"Word problems\", the topic \"Travel and Distance problems\".\r
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