document.write( "Question 1125847: Can anyone help me set this up and solve? I am having some trouble with this conceot. Thank you.\r
\n" ); document.write( "\n" ); document.write( "Alvin paddled for 2 hours with a 6-km/h current to reach a campsite. The return trip against the same current took 8 hours. Find the speed of the boat in still water. \n" ); document.write( "
Algebra.Com's Answer #742159 by ikleyn(52780)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Let u be he speed of the boat in still water.\r\n" );
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document.write( "Then the effective speed downstream is u+6 km/h.\r\n" );
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document.write( "So the distance downstream is  2*(u+6) kilometers.\r\n" );
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document.write( "The effective speed upstream is  (u-6) km/h.\r\n" );
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document.write( "So the distance upstream is     8*(u-6) kilometers.\r\n" );
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document.write( "Each way distance is the same, which gives you an equation\r\n" );
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document.write( "    2*(u+6) = 8*(u-6).\r\n" );
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document.write( "Simplify and solve it:\r\n" );
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document.write( "    2u + 12 = 8u - 48,\r\n" );
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document.write( "    12 + 48 = 8u - 2u\r\n" );
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document.write( "    60  = 6u    ====>  u = 60/6 = 10 kilometer per hour.\r\n" );
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document.write( "Answer.  The speed of the boat in still water is  10 km/h.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "Make a check on your own - and you will understand the solution even better.\r
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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
\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, where you will find other similar solved problems with detailed explanations.\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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