Question

A can do a piece of work in 4days. B can do it in 5dyas. with he assisment of C they completed the work in two days. find how many days can C alone do it?

Answer 1

Answer: 20 days

Explanation:

A = 1/4 of work per day

B = 1/5 of work per day

A + B + C = 1/2 of work per day

C = 1/2 - (1/4 + 1/5)

= 10/20 - (5/20 + 4/20)

= 10/20 - 9/20

= 1/20

Therefore, C can do only 1/20 of work per day.

Total no. of days required to complete work = 20 days.