document.write( "Question 1138481: One computer can solve a problem 5 minutes faster than a second computer. Working together, the computers can solve the problem in 6 minutes. How long does it take the faster computer working alone to solve the problem?
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Algebra.Com's Answer #756274 by ikleyn(52786) $\"\"$ $\"About$

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document.write( "Let x be the time for the faster computer to do the job working alone (in minutes).\r\n" );
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document.write( "Then the time for slower compute is (x+5) minutes, according to the condition.\r\n" );
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document.write( "Then their individual rates are   and  , giving the combined rate equal to the sum of individual rates.\r\n" );
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document.write( "It gives you an equation\r\n" );
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document.write( "     +  = \r\n" );
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document.write( "To solve it, multiply both sides by 6x*(x+5). You will get\r\n" );
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document.write( "    6(x+5) + 6x =  x*(x+5)\r\n" );
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document.write( "    6x + 30 + 6x = x^2 + 5x\r\n" );
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document.write( "    x^2 - 7x - 30 = 0\r\n" );
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document.write( "    (x-10)*(x+3) = 0\r\n" );
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document.write( "The roots are 10 and -3, and only positive root is meaningful.\r\n" );
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document.write( "Answer.  The faster computer makes this job in 10 minutes, working alone.\r\n" );
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document.write( "CHECK.    +  =  +  =  =  = .   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is a standard and typical joint work problem.\r
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\n" ); document.write( "\n" ); document.write( "There is a wide variety of similar solved joint-work problems with detailed explanations in this site.
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\n" ); document.write( "\n" ); document.write( "    - Using Fractions to solve word problems on joint work \r
\n" ); document.write( "\n" ); document.write( "    - Solving more complicated word problems on joint work \r
\n" ); document.write( "\n" ); document.write( "    - Selected joint-work word problems from the archive \r
\n" ); document.write( "\n" ); document.write( "    - Using quadratic equations to solve word problems on joint work (*)\r
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\n" ); document.write( "\n" ); document.write( "Of this list, the most relevant problems are in the lesson marked by (*).\r
\n" ); document.write( "\n" ); document.write( "Read them and get be trained in solving joint-work problems.\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 topic
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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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