Question

A and b can do a work in 12 days, b and c in 15 days, c and a in 20 days. If a, b and c work together, they will complete the work in: option 1 : 5 days option 2 : 47/6 days option 3 : 10 days option 4 : 47/3 days

Answer 1

a b and c together can do 1/10 work in 1 day then they complete whole work in 10 days