document.write( "Question 1147334: A motorboat maintained a constant speed of
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Algebra.Com's Answer #768701 by ikleyn(52797) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "If the speed of the current is \"x\" miles per hour, then\r\n" );
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document.write( "    - the effective rate of the motorboat upstream is   (24-x) mph, while\r\n" );
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document.write( "    - the effective rate of the motorboat downstream is (24+x) mph.\r\n" );
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document.write( "Then the time moving upstream is    hours, while\r\n" );
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document.write( "     the time moving downstream is    hours.\r\n" );
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document.write( "The total time is 1 hour, giving you this \"time\" equation\r\n" );
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document.write( "      +  = 1  hour.\r\n" );
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document.write( "To solve it, multiply both sides by (24-x)*(24+x).  You will get\r\n" );
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document.write( "     9*(24+x) + 9*(24-x) = .\r\n" );
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document.write( "Simplify step by step\r\n" );
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document.write( "     9*24 + 9x + 9*24 - 9x = ,\r\n" );
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document.write( "     2*9*24                = \r\n" );
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document.write( "      =  = 24*(24-2*9) = 24*6 = 12*12 = .\r\n" );
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document.write( "It implies  x =  = 12.\r\n" );
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document.write( "ANSWER.  The speed of the current is 12 miles per hour.\r\n" );
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document.write( "CHECK.    +  =  +  =  +  = 1 hour.    ! Precisely correct !\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( "    - 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
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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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