document.write( "Question 551677: It would take Maricar 10 hours working alone to clean all hotel rooms, while it would take Marivic only 8 hours. How long would it take them to do the job together? \n" ); document.write( "
Algebra.Com's Answer #359846 by Edwin McCravy(20055)\"\" \"About 
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It would take Maricar 10 hours working alone to clean all hotel rooms, while it would take Marivic only 8 hours. How long would it take them to do the job together?
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document.write( "Let the desired time be x\r\n" );
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document.write( "Make this chart and put x for the time required working together, and 10 and\r\n" );
document.write( "8 for the times for them working separately.\r\n" );
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document.write( "                        Number of        Number of          Rate in\r\n" );
document.write( "                       jobs done       hours required      jobs/hour\r\n" );
document.write( "Maricar working alone                        10 \r\n" );
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document.write( "Marivic working alone                         8\r\n" );
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document.write( "Both working together                         x\r\n" );
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document.write( "In all three cases 1 job is being done, so we fill in 1 for the number\r\n" );
document.write( "of jobs:\r\n" );
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document.write( "                        Number of        Number of          Rate in\r\n" );
document.write( "                       jobs done       hours required      jobs/hour\r\n" );
document.write( "Maricar working alone      1                 10 \r\n" );
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document.write( "Marivic working alone      1                  8\r\n" );
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document.write( "Both working together      1                  x\r\n" );
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document.write( "Fill in the rates in jobs/hour by dividing jobs done by hours:\r\n" );
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document.write( "                        Number of        Number of          Rate in\r\n" );
document.write( "                       jobs done       hours required      jobs/hour\r\n" );
document.write( "Maricar working alone      1                 10              \"1%2F10\" \r\n" );
document.write( "Marivic working alone      1                  8              \"1%2F8\" \r\n" );
document.write( "Both working together      1                  x              \"1%2Fx\"\r\n" );
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document.write( "           The equation comes from\r\n" );
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document.write( "                 \"%28matrix%284%2C1%2C%22Maricar%27s%22%2C+rate%2Cworking%2Calone%29%29\" + \"%28matrix%284%2C1%2C%22Marivic%27s%22%2C+rate%2Cworking%2Calone%29%29\" = \"%28matrix%285%2C1%2Crate%2C+of%2Cboth%2Cworking%2Ctogether%29%29\"\r\n" );
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document.write( "                              \"1%2F10\" + \"1%2F8\" = \"1%2Fx\"\r\n" );
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document.write( "Solve that equation and get \"40%2F9\" or \"4%264%2F9\" hours or\r\n" );
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document.write( "4 hours, 26 minutes and 40 seconds.\r\n" );
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document.write( "Edwin
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