SOLUTION: This ones killing me.....lol thank you... A,B and C can finish a job in 6 days.If B and C work together, the job will take 9 days; if A and C work together, the job will take 8

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Question 130052: This ones killing me.....lol thank you...
A,B and C can finish a job in 6 days.If B and C work together, the job will take 9 days; if A and C work together, the job will take 8 days. In how many days can each man working alone do the job?
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
(combined time)/(individual's time)=(individual's job fraction)
__ all the fractions sum to 1, the whole job

%286%2FA%29%2B%286%2FB%29%2B%286%2FC%29=1

%289%2FB%29%2A%289%2FC%29=1 __ multiplying by 2/3 __ %286%2FB%29%2B%286%2FC%29=2%2F3
__ substituting __ %286%2FA%29%2B%282%2F3%29=1 __ subtracting 2/3 __ 6%2FA=1%2F3
__ "cross" multiplying __ 18=A

%288%2FA%29%2B%288%2FC%29=1 __ multiplying by 3/4 __ %286%2FA%29%2B%286%2FC%29=3%2F4
__ substituting __ %286%2FB%29%2B%283%2F4%29=1 __ subtracting 3/4 __ 6%2FB=1%2F4
__ "cross" multiplying __ 24=B

substituting __ %281%2F3%29%2B%281%2F4%29%2B%286%2FC%29=1 __ %287%2F12%29%2B%286%2FC%29=1 __ subtracting 7/12 __ 6%2FC=5%2F12
__ "cross" multiplying __ 72=5C __ dividing by 5 __ 14.4=C