A and B can do a piece of work in 12 days and 15 days respectively. They began to work together but A left after 4 days. In how many more day would B alone complete the remaining work ?
(a) 20/3 days
(b) 25/3 days
(c) 6 days
(d) 5 days
Correct option (c) 6 days
Explanation:
Total work done by A and B in 4 days is (5+4)× 4
= 36 units
Total work left = 60-36 =24 units
And B will complete this in = 24/4 = 6 days
