document.write( "Question 1170604: It takes Robert 9 hours longer to construct a fence than it takes Eldin. If they work together,
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Algebra.Com's Answer #795451 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "It takes Robert 9 hours longer to construct a fence than it takes Eldin. If they work together, they can construct the fence in 20 hours. How long would it take each, working alone, to construct the fence?
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Let time it takes Robert to do the job, be R
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document.write( "Then time it takes Eldin is: R - 9
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document.write( "Therefore, Robert can do  of job in 1 hour, while Eldin can do  of job in 1 hour
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document.write( "We then get the following equation: 
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document.write( "20(R - 9) + 20R = R(R - 9) ------- Multiplying by LCD, 20R(R - 9)
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document.write( "(R - 45)(R - 4) = 0
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document.write( "Robert's time to complete job, alone:                 OR                 R = 4 (ignore)
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document.write( "Eldin's time to complete job, alone:  \n" );
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