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Q:
A) 20days | B) 40 days |
C) 50 days | D) 60 days |
Answer: D) 60 days
Explanation:
Explanation:
(A+B)'s 1 day's work=1/20
C's 1 day work=1/60
(A+B+C)'s 1 day's work= 1/20 + 1/60 = 1/15
Also A's 1 day's work =(B+C)'s 1 day's work
Therefore, we get: 2 x (A's 1 day 's work)=1/15
=>A's 1 day's work=1/30
Therefore, B's 1 day's work= 1/20 - 1/30 = 1/60
So, B alone could do the work in 60 days.