Question

(A+B) do 1 work in 12 days
(B+C) do 1 work in 15 days
(C+A). do 1 work in 20 days
In how many days (A+B+C) do 1 work ?​

Answer 1

Answer:

(A+B) + (B+C) + (A+C) = 1/12 + 1/15 + 1/20

2 (A+B+C) = 12/60

On simplification, we get

(A+B+C) = 1/10

It means that,

In 1 day, (A+B+C) together can do 1/10th of the work.

So, to complete one piece of work together, it will take 10 days.