Question

A can do a piece of work in 18 days and B can do same work in 24
days. In how many days can they complete it? If they do it together.​

Answer 1

Answer:

A and B together can complete a piece of work in 18 days, B and C in 24 days and A and C in 36 days. In how many days, will all of them together complete the work? ∴ A, B and C together will complete the work in 16 days. Hence option [D] is correct answer

Answer 2

i think so that the answer is

21 days