A can do a piece of work in 10 days. B is 50% more efficient than A. In how many days B alone can do the same job?

Question: A can do a piece of work in 10 days. B is 50% more efficient than A. In how many days B alone can do the same job?

Solution:
B is 50% more efficient than A so he will take less time to do a piece of work.

Therefore, the ratio of the time taken by A and B = 150/100 = 3 : 2

Let B takes X days to do the job.
3 : 2 = 10 : X
⇒ 3X =20
∴ X = 6.6 days