It is given that
A can do a piece of work in 4 days
B can do the same work in 5 days
A’s one day work = 14
B’s one day work = 15
(i) A and B both one day work = 14+15
Taking LCM
= (5 + 4)/ 20
= 9/ 20
(ii) A and B two days’ work = 9/20 × 2 = 9/10
So the work left after 2 days = 1 – 9/10
Taking LCM
= (10 – 9)/ 10
= 1/10