Question

Dolly is 35% more efficient than Debasmita, and Debasmita takes 21 days more than Dolly to complete a piece of work. How many days will Dolly take to complete the same work?
1. 81
2. 40
3. 60
4. 68

Answer 1

Correct Answer - Option 3 : 60

Given:

Efficiency of Dolly = 35% more than efficiency of Debasmita

Time taken by debasmita = 21 days more than time taken by Dolly

Concept:

Efficiency is inversely proportional to the time.

Calculation:

Ratio of efficiency of Dolly and Debasmita = 135 ∶ 100

Ratio of time taken by Dolly and Debasmita = 100 ∶ 135

Let Dolly takes 100x days, and Debasmita takes 135x days to complete a piece of work.

Days taken by Debasmita – Days taken by Dolly = 21

⇒ 135x – 100x = 21

⇒ 35x = 21

⇒ x = 3/5

Days taken by Dolly = 100x

⇒ 100 × 3/5

⇒ 60

∴ Dolly will take 60 days to complete the same work.