document.write( "Question 1117060: Lumi rides her boat 13km upstream and back in the same period of time. She rides 30km downstream, if the rate (speed) of the current is 5km/h. Find the rate of lumi's boat in still water. \n" ); document.write( "

Algebra.Com's Answer #732024 by ikleyn(53937) $\"\"$ $\"About$

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document.write( " +  =     <<<---=== it is your basic \"time\" equation\r\n" );
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document.write( " =  - \r\n" );
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document.write( " = \r\n" );
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document.write( "13*(u+5) = 17*(u-5)\r\n" );
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document.write( "13u + 65 = 17u - 85\r\n" );
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document.write( "65 + 85 = 17u - 13u\r\n" );
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document.write( "150 = 4u  ====>  u =  = 37.5.\r\n" );
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document.write( "Answer.  The rate of lumi's boat in still water is  37.5 km/h.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "On similar problems, 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( "    - 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( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\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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