# A is twice efficient as of B and B is thrice efficient as of C. then they work together and complete the whole work in 15 days. In how many days C can

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A is twice efficient as of B and B is thrice efficient as of C. then they work together and complete the whole work in 15 days. In how many days C can complete the work alone?
1. 300 days
2. 200 days
3. 150 days
4. 140 days
5. 120 days

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Correct Answer - Option 3 : 150 days

Given:

A is twice efficient as of B and B is thrice efficient as of C.

Time taken to complete the whole work = 15 days

Formula used:

Efficiency = Total work/TIme

Calculation:

Efficiency of A and B = 2 : 1      ----(1)

Efficiency of B and C = 3 : 1     ----(2)

Eq. (1) × 3 and Eq. (2) × 1; then solve:

⇒ Efficiency of A : B : C = 6 : 3 : 1

Total efficiency = 6 + 3 + 1 = 10 units/day

⇒ Total work = 15 days × 10 units/day

⇒ Total work = 150 units

Time taken by C to complete the whole work = 150/1 = 150 days

C complete the whole work in 150 days.