document.write( "Question 1001707: A and B together can finish a job in 36 days. If A can do as much
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Algebra.Com's Answer #618802 by Edwin McCravy(20059) $\"\"$ $\"About$

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The question is:
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document.write( "Let x = the number of days it takes for A to do 1 job.\r\n" );
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document.write( "Then A's rate in jobs per day is 1 job per x days or 1/x jobs per day.\r\n" );
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document.write( "Let y = the number of days it takes for B to do 1 job.\r\n" );
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document.write( "Then B's rate in jobs per day is 1 job per y days or 1/y jobs per day.\r\n" );
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\n" ); document.write( "A and B together can finish a job in 36 days.
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document.write( "Then their combined rate is 1 job per 36 days, or 1/36 jobs per day.\r\n" );
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document.write( "The sum of their rates equals 1/36 jobs per day.\r\n" );
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document.write( "1/x + 1/y = 1/36\r\n" );
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\n" ); document.write( "If A can do as much work in 4 days as B can do in 9 days,
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document.write( "We use rate×time to determine what part of a job is done by A\r\n" );
document.write( "in 4 days and what part of a job is done by B in 9 days, and\r\n" );
document.write( "set those equal to each other:\r\n" );
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document.write( "4/x = 9/y\r\n" );
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document.write( "or\r\n" );
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document.write( "4/x - 9/y = 0\r\n" );
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document.write( "The system of equations is\r\n" );
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document.write( "Do not clear of fractions. Instead eliminate 1/y\r\n" );
document.write( "by multiplying the first equation through by 9\r\n" );
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document.write( "Adding the two equations:\r\n" );
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document.write( "cross multiply \r\n" );
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document.write( "x = 52 days = how many days it takes for A to do the job.\r\n" );
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document.write( "Substitute in\r\n" );
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document.write( "Cross multiply\r\n" );
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document.write( "y = 117 days = how many days it takes for B to do the job.\r\n" );
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document.write( "Edwin

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