Question

If a b does work in 12 days b and c in 15 days and c and a does work in 20 days.What is the time taken by a,b and c to compelete the work?

Answer 1

Step-by-step explanation:

a+b=1/12,b+c=1/15,c+a=1/20

a+b+b+c+c+a=1/12+1/15+1/20

2a+2b+2c=5+4+3/60

2(a+b+c)=12/60

2(a+b+c)=1/5

a+b+c=1/15×2

a+b+c=1/30