Correct Answer - Option 4 : B
Given:
Ratio of efficiency of Ullas to Tejas = 2 : 1
Time to complete the whole work together = 18 days
Formula used:
Efficiency = (Total work)/(Time Taken)
Calculations:
Let the efficiency of Ullas and Tejas be 2 units/day and 1 unit/day respectively.
Combined efficiency of Ullas and Tejas together = 2 + 1 = 3 units/day
Efficiency = (Total work)/(Time Taken)
⇒ 3 = (Total work)/18
⇒ Total work = 54 units
Time to complete the whole work by Tejas alone = 54/1 = 54 days
∴ Tejas will complete the same work alone in 54 days.