Correct Answer - Option 1 : 51/2 days
Given:
The efficiency of A, B and C are in the ratio 4 ∶ 6 ∶ 7.
A, B and C can complete a work in 18 days.
Concept used:
Total work = Efficiency × Time
Calculation:
Efficiency ratio,
A ∶ B ∶ C = 4 ∶ 6 ∶ 7
According to the question,
Total work = Efficiency × Time
⇒ Total work = (4 + 6 + 7) × 18
⇒ Total work = 17 × 18 = 306
TimeB = 50% of the total work/efficiency of B
⇒ TimeB = {306 × (50/100)}/6
⇒ TimeB = 153/6 = 51/2 days
∴ B can alone complete 50% of the work in 51/2 days.
