A and B together can complete a work in 12 days, B and C together can complete a work in 40 days and A and C together can complete a work in 30 days. If they all work together then how many days would it take to complete the work?

A and B together can complete a work in 12 days, B and C together can complete a work in 40 days and A and C together can complete a work in 30 days. If they all work together then how many days would it take to complete the work? Correct Answer 240/17

Given:

A + B can complete a work in 12 days

B + C can complete a work 40 days

A + C can complete a work in 30 days

Formula used:

Efficiency = Total work/Total time

Calculation:

Let the total work be 1 unit.

(A + B)`s one days` work = 1/12

(B + C)`s one days` work = 1/40

(A + C)`s one days` work = 1/30

⇒ 2(A + B+ C)`s one day`s work = (1/12 + 1/40 + 1/30)

⇒ (A + B+ C)`s one day`s work = (10 + 3 + 4)/240

⇒ 17/240

Time to complete whole work together = 1/(17/240) = 240/17 days

∴ A, B, C together can complete the work in 240/17 days.

Related Questions

Each question below is followed by two statements I and II. You have to determine whether the data given in the statement is sufficient for answering the question. You should use the data and your knowledge of Mathematics to choose the best possible answer. P, Q and R together can complete a work in 12 days. All of them worked together for 6 days and then P left. How much time will Q and R together will take to complete the remaining work? I. If P completes a work in X number of days, then Q and R together complete the work in X number of days. II. After leaving the work, P completed another work in 10 days.