X and Y can do a job in 18 days; Y and Z can do the same in 24 days. If all three can finish the job in 12 days, in how many days can X and Z complete the job?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. days.
Work done by Y in 1 day = 1/18 + 1/24 - 1/12 = 1/72
Work done by X and Z in 1 day = 1/12 - 1/72 = 5/72
Time required for X and Z to complete the job = 72/5 = days