A can do a piece of work in 6 days and B can do it in 8 days. How long will they take to complete it together ?
Answers:
A can do a work in = 6 days
∴ A’s one day’s work = 1/6
B can do the same work in = 8 days
∴ B is one day’s work = 1/8
∴ A and B’s both one day’s work = 1/6 + 1/8
= (4 + 3)/24
= 7/24
∴ Both A and B can do the same work in 24/7 = 3.3/7 days