1.  X can do a work in 16 days. In how many days will the work be completed by Y, if the efficiency of Y is 60% more than that of X ?
A. 10 days
B. 12 days
C. 25 days
D. 30 days

Answer: Option A

Explanation:

Ratio of time taken by X

and Y = 160 : 100 = 16 : 1

Suppose Y takes y days to the work.

Then, 1.6 : 1 = 16 : y

∴ y = (16 x 1)/1.6 = 10 days