document.write( "Question 1132152: Dan can do the job in 30 hours, Ellen can do it in 40 hours, and Francis can do it in 60 hours. How long would it take them if they work together? (use only one variable)(thanks in advance) \n" ); document.write( "

Algebra.Com's Answer #749130 by ikleyn(52778) $\"\"$ $\"About$

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document.write( "Dan     makes    of the entire job per hour.  It is his rate of work.\r\n" );
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document.write( "Ellen   makes    of the entire job per hour.  It is her rate of work.\r\n" );
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document.write( "Francis makes    of the entire job per hour.  It is his (or her (?) ) rate of work.\r\n" );
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document.write( "Working together, the tree persons make   =  =  =   of the entire job per hour.\r\n" );
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document.write( "    It is their COMBINED rate of work, which is the sum of the individual rates.\r\n" );
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document.write( "To solve the problem using one variable, introduce t as the time it takes them to complete the entire job working together.\r\n" );
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document.write( "Then your equation is  Time*Rate = the entire job,  or\r\n" );
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document.write( "     = 1,\r\n" );
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document.write( "which implies\r\n" );
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document.write( "    t =  =  =  hours = 13 hours and 20 minutes.    ANSWER\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. See the lessons\r
\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
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\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
\n" ); document.write( "\"Rate of work and joint work problems\" of the section \"Word 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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