Hamza can do a work in 15 days and Aslam in 12 days. If they work on it together for 4 days, the fraction of work that is left is________?

2/5

3/5

4/7

1/5

1/4

Explanation

Part of work completed by Hamza in a day = 1/15 Part of work completed by Aslam in a day = 1/12 Part of work completed by them in a day = (1/15)+(1/12) = 3/20 Part of work completed by them in 4 days = (3/20)*4 = 3/5 Fraction of work left

= 1-(3/5)
= 2/5