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Question
A, B and C together finish a work in 4 days. If A alone can finish the same work in 8 days and B in 12 days, find how long will C take to finish the work.
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Solution
A. B and C finish work together in = 4 days.
A. B and C finish work together in 1 day = `1/4`
A' one day work = `1/8`
B's one day work = `1/12`
∴ C's one day work `= 1/4 - (1/8 + 1/12)`
`= (6 - (3 + 2))/24 = 1/24`
∴ C can finish the work in = 24 days
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