Question

A is finish work 15 days and Ab is finish the work 9days how much days to finish that work b

Answer 1

A finishes work in one day=1/15
Both finish in one day=1/9
Contribution of B =
total work done- A's work
= 1/9-1/15
= 2/45(in one day)
So entire work will be done by B = 22.5 days

Answer 2

ab = 9
a = 15
b =?
A works for one day =1÷15
AB works for one day =1÷9
therefore B works in one day =2÷45
therefore B completes work in 22.5 days