X alone can complete a work in 18 days and Y alone can do the same work in half time of the time taken by X. Working together, what part of the same work can they complete in a day?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 1/6.
Y alone can complete the work in 9 days
Total work = 18 (LCM of 18 and 9)
Total efficiency of X and Y = (18/18) + (18/9) = 1 + 2 = 3 units/day
Part of the work done by X and Y in one day = 3/18 = 1/6