Correct Answer - Option 3 : 60 days
Given
Pooja is twice as efficient as Aarti and takes 90 days less than Aarti to complete the job.
Concept used
Time and work
Calculation
Total work = Number of days × Efficiency
Efficiency of Pooja and Aarti = 2 : 1
Pooja takes 90 days less than Aarti
⇒ 2(90 - x) = 1x
⇒ 180 - 2x = x
⇒ x = 60
Total work = 60 × (2 + 1) = 180 units
Together they can do the work in
⇒ 180 / 3 = 60 Days.