'A' and 'B' complete a work togather in 8 days.If 'A' alone can do it in 12 days.Then how many day 'B' will take to complete the work?

'A' and 'B' complete a work togather in 8 days.If 'A' alone can do it in 12 days.Then how many day 'B' will take to complete the work?

A. 25 days
B. 24 days
C. 20 days
D. None of these









Option B

Explanation:
A & B one day work = 1/8 
A alone one day work = 1/12
B alone one day work = (1/8 - 1/12) = ( 3/24 - 2/24) 
=> B one day work = 1/24
so B can complete the work in 24 days.