Correct Answer - Option 4 : 32 days
Given:
A is 50% more efficient than B, B is 25% less efficient than C. If C can complete a work in 30 days
Concept Used:
Total Work = Efficiency × Time
Calculation:
50% more = + 1/2, 25% less = - 1/4
Take efficiency of C= 2 × 4 = 8
Suppose efficiency of C = 8
The efficiency of B (EB) = 75% of C = 3/4 × 8 = 6
The efficiency of A (EA) = 150% of B = 3/2 × 6 = 9
Days taken by C to complete the work = 30
⇒ Total Work = Efficiency × Days = 8 × 30 = 240
Now, EA = 9, EB = 6
Work on the first day by A = 9 [∵ A starts the work]
Work on the second day = 6
Thus, Work in 2 days = 9 + 6 = 15
Total time to complete the work (240/15) × 2 [∵ 15 unit work done in 2 days]
⇒ 16 × 2 = 32 days
∴ The work will complete in 32 days.