document.write( "Question 1105953: A boat takes 2/3 as much time to travel downstream as to its return. If the rate of the river's current is 8 kph, what is the rate of the boat i still water? \n" ); document.write( "

Algebra.Com's Answer #720863 by ikleyn(52786) $\"\"$ $\"About$

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\n" ); document.write( "A boat takes 2/3 as much time to travel downstream as to its return. If the rate of the river's current is 8 kph,
\n" ); document.write( "what is the rate of the boat $\"highlight%28cross%28i%29%29\"$ in still water?
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document.write( "Let  \"x\"  be the the rate of the boat in still water.\r\n" );
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document.write( "Then its effective rate downstream is (x+8) km/h,\r\n" );
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document.write( "while the effective rate upstream is (x-8) km/h.\r\n" );
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document.write( "The \"time equation\" is \r\n" );
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document.write( " = ,       (<<<---=== it says \"time downstream = 2/3 time upstream\")\r\n" );
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document.write( "where D is one way distance.\r\n" );
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document.write( "You can cancel the factor D.  After that, multiply both sides by  3*(x-8)*(x+8)  to get\r\n" );
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document.write( "3*(x-8) = 2*(x+8),\r\n" );
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document.write( "3x - 24 = 2x + 16,\r\n" );
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document.write( "3x - 2x = 16 + 24  ====>  x = 40.\r\n" );
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document.write( "Answer.  the rate of the boat in still water is 40 km/h.\r\n" );
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\n" ); document.write( "It is a typical and standard Upstream and Downstream round trip word problem.\r
\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
\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( "    - Wind and Current problems solvable by quadratic equations \r
\n" ); document.write( "\n" ); document.write( "    - Unpowered raft floating downstream along a river\r
\n" ); document.write( "\n" ); document.write( "    - Selected problems from the archive on the boat floating Upstream and Downstream \r
\n" ); document.write( "\n" ); document.write( "in this site.\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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\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
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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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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