B. 22+(1/2)days
Feedback Ratio of times taken by A and B = 1 : 3.
The time difference is (3 - 1) 2 days while B take 3 days and A takes 1 day.
If difference of time is 2 days, B takes 3 days.
If difference of time is 60 days, B takes(3/2x 60= 90 days.
So, A takes 30 days to do the work.
A's 1 day's work =1/30
B's 1 day's work = 1/90
(A + B)'s 1 day's work =(1/30 + 1/90) =4/90 = 2/45
A and B together can do the work in 45/2 =22(1/2) days