Correct Answer - Option 1 : 30 days

**Given:**

A is 25% more efficient than A, B takes 6 days more than A to complete a piece of work.

**Concept:**

Efficiency is inversely proportional to the time.

**Calculation:**

Ratio of efficiency of A and B = 125 ∶ 100

Ratio of time taken by A and B = 100 ∶ 125

Let A takes 100x days, and B takes 125x days to complete a piece of work.

Days taken by B – Days taken by A = 6

⇒ 125x – 100x = 6

⇒ 25x = 6

⇒ x = 6/25

Days taken by A = 100x

⇒ 100 × 6/25

⇒ 4 × 6

⇒ 24

And, days taken by B = 125x

⇒ 125 × 6/25

⇒ 5 × 6

⇒ 30

**∴**** B will take 30 days to complete the same work.**