Sakshi can do a piece of work in 20 days. Tanya is 25% more efficient than Sakshi. The number of days taken by Tanya to do the same piece of work is:

Answer: Option B

Ratio of times taken by Sakshi and Tanya
= 125 : 100
= 5 : 4
Suppose Tanya takes x days to do the work
5 : 4 :: 20 : x
⇒ $$x=\frac{4\times 20}{5}$$
⇒ x = 16 days
Hence, Tanya takes 16 days to complete the work