Question 796610
A father and his son can clean the house together in 4 hours. When the son works alone, it take him an hour longer to clean than it takes his dad alone. find how long it takes the son to clean alone.
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Together rate: 1/4 job/hr
Dad's rate: 1/x job/hr
Son's rate: 1/(x+1) job/hr
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Equation:
rate + rate = together rate
1/x + 1/(x+1) = 1/4
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4(x+1) + 4x = x(x+1)
8x + 4 = x^2+x
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x^2 - 4x -4 = 0
x = 4.8284 hrs 
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x+1 = 5.8284 hrs (Son's time to do the job alone)
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Cheers,
Stan H.
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