document.write( "Question 1148597: A motorboat takes
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Algebra.Com's Answer #769943 by ikleyn(52781)\"\" \"About 
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document.write( "Let \"u\" be the rate of the boat in still water,\r\n" );
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document.write( "and let \"v\" be the rate of the current.\r\n" );
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document.write( "Then\r\n" );
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document.write( "    u + v = \"100%2F2\" = 50 mph is the effective rate moving downstream, and\r\n" );
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document.write( "    u - v = \"100%2F5\" = 20 mph is the effective rate moving upstream.\r\n" );
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document.write( "Add the equations to get \r\n" );
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document.write( "    2u = 50+20 = 70 mph,   u = 70/2 = 35 mph.\r\n" );
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document.write( "Substitute the found value of \"u\" into the first equation to get\r\n" );
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document.write( "    v = 50 - 35 = 15 mph.\r\n" );
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document.write( "ANSWER.   The rate of the motorboat in still water is 35 mph; the rate of the current is 15 mph.\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is a typical and standard Upstream and Downstream round trip word problem.\r
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\n" ); document.write( "\n" ); document.write( "You can find many similar fully solved problems on upstream and downstream round trips with detailed solutions in lessons \r
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\n" ); document.write( "\n" ); document.write( "    - Unpowered raft floating downstream along a river\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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\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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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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