Correct Answer - Option 5 : None of these.
Given:
Efficiency of Amar, Ujjwal and Chitrakshi = 2 : 3 : 5
Amar alone can complete the work in = 150 days
Formula:
Total work = Efficiency × Time
Calculation:
Efficiency of Amar, Ujjwal and Chitrakshi = 2 : 3 : 5
Total work = 2 × 150 = 300 units
Work done by Amar, Ujjwal and Chitrakshi in 15 days = (2 + 3 + 5) × 15
⇒ 10 × 15
⇒ 150 units
Remaining work = 300 – 150 = 150 units
Efficiency of Amar and Ujjwal = 2 + 3 = 5 units
Time taken by Amar and Ujjwal to complete the remaining work = 150/5
⇒ 30 days
∴ Amar and Ujjwal together can complete the remaining work in 30 days.