(Solved) A alone can do a work in 12 days while A and B together can do that work in 7.5 days. Find the time taken by C alone to do that work if C takes 3 days more than that of B alone to do that work? (a) 33 days (b) 30 days (c) 23 days (d) 27 days (e) 28 days

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 Question :

A alone can do a work in 12 days while A and B together can do that work in 7.5 days. Find the time taken by C alone to do that work if C takes 3 days more than that of B alone to do that work?

(a) 33 days

(b) 30 days

(c) 23 days

(d) 27 days

(e) 28 days


Solution :

Let B alone take x days to do the work

A and B together in 1 days do

1/x = 1/7.5 - 1/12

1/x = 10/75 - 1/12

1/x = 2/15 - 1/12

1/x = 24 - 15/180

1/x = 9/180

1/x = 1/20

X = 20 days


B alone done work = 20 days

Here, c takes 3 days more than B

20+3

23 days

C alone = 23 days


 Here answer is option c =23 days. 

For further queries please comment below. 


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