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# A, B, and C together can do a work in 3 days. If A or B alone can do

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Re: A, B, and C together can do a work in 3 days. If A or B alone can do [#permalink]
Ans B 12 Days

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Re: A, B, and C together can do a work in 3 days. If A or B alone can do [#permalink]
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Bunuel wrote:
A, B, and C together can do a work in 3 days. If A or B alone can do the work in 8 days, then how long will C take alone to do the same work?

(A) 27 days
(B) 12 days
(C) 5 days
(D) 2 days
(E) 1 day

Solution:

We know that the daily rate of A alone is 1/8, and the daily rate of B alone is also 1/8. If we let c = the number of days it takes C to complete the work alone, we can create the equation:

1/8 + 1/8 + 1/c = 1/3

Multiplying the equation by 24c, we have:

3c + 3c + 24 = 8c

24 = 2c

12 = c