Athar can do a certain work in the same time in which Baban and Chetan together can do it. If Athar and Baban together could do it in 10 days and Chetan alone in 50 days, then Baban alone could do it in:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 25 days.
Let A’s 1-day work = 1/A, B’s = 1/B, and C’s = 1/C
1/A = 1/B + 1/C ...(1)
1/A + 1/B = 1/10 ...(2)
1/C = 1/50 ...(3)
From (1): 1/A = 1/B + 1/50 ...(4)
From (2) and (4): (1/B + 1/50) + 1/B = 1/10
⇒ 2/B + 1/50 = 1/10
⇒ 2/B = 1/10 – 1/50 = 2/25
⇒ 1/B = 1/25
Time required for B alone = 25 days