Question 728073
    craig and jim,working together, can clean the house in 2 hours. Working alone, jim takes twice as long as craig. How long does it take craig to clean the house alone?
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Let x = time (hours) it takes Craig to clean the house alone
then
2x = time (hours) it takes Jim to clean the house alone
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The equation:
2(1/x + 1/(2x)) = 1
multiplying both sides by 2x:
2(2 + 1) = 2x
2(3) = 2x
6 = 2x
3 hours = x (Time it takes Craig)