X , Y and Z can complete a work in 5 days, 15 days and 30 days, respectively. In how days can the work be completed if X is assisted by Y and Z together, on every second day?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 4 days.
Let the total work be LCM(5, 15, and 30) = 30 units
Work completed by X in 1 day =
Work completed by Y in 1 day =
Work completed by Z in 1 day =
Y and Z help x on every 2nd day
Hence, work completed in 2 days = 6 + 9 = 15 units
They will complete 30 units in = = 4 days.