X can completed a job in 12 days. If X and Y work together, they can complete the job in 6 2/ 3 days, Y alone can complete the job in
Correct Answer: 15 days
Explanation:
X's 1 day's work = 1/12
(X + Y)' s 1 day's work = 3/20
∴ Y's 1 day's work = (3/20) - (1/12) = 4/60 = 1/15
∴ Number of day's taken by Y to complete the work = 15 days
