A and B can together do a piece of work in 15 days. B alone

Home » Aptitude » Time and Work » Question

A and B can together do a piece of work in 15 days. B alone can do it 20 days. In how many days can A alone do it ?

1. 30 days
2. 40 days
3. 45 days
4. 60 days

Correct Option: D

A's 1 day's work = (1/15 - 1/20) = 1/60
∴ A alone can finish it in 60 days.