1 Answers
Option 2 : B
Given:
The ratio of efficiencies of A, B, and C is 3 : 2 : 1.
Working together they can complete the work in 4 days.
A + B worked for 2 days.
B + C worked for 2 days.
Then total work is completed in next 4 days.
Formula Used:
Efficiency = Total Work/Time taken
Total Units of Work = Efficiency × Time taken
Calculation:
Let the efficiency of A, B, and C be 3, 2, and 1 respectively.
They worked together and completed the work in 4 days.
Total Units of work = Total efficiency × 4 days
⇒ Total Units of work = (3 + 2 + 1) × 4
⇒ Total Units of work = 6 × 4
⇒ Total Units of work = 24 units
A + B worked for 2 days.
Total Units of work completed by them,
⇒ Total units of work = (A + B) × 2 days
⇒ Total units of work = (3 + 2) × 2
⇒ Total units of work = 5 × 2
⇒ Total units of work = 10 units.
B + C worked for 2 days.
Total Units of work completed by them,
⇒ Total units of work = (B + C) × 2 days
⇒ Total units of work = (2 + 1) × 2
⇒ Total units of work = 3 × 2
⇒ Total units of work = 6 units.
Total units of work completed,
⇒ 10 units + 6 units
⇒ 16 units
Remaining units of work = 24 units – 16 units
⇒ Remaining units of work = 8 units
Remaining work completed in 4 days.
8 units of work completed in 4 days.
⇒ Efficiency = Total work/Time taken
⇒ Efficiency = 8/4
⇒ Efficiency = 2
⇒ The efficiency of B was 2 units
∴ For the last 4 days, B had worked to complete the work.