Correct Answer - Option 3 : 67 years

**Given****∶**

20 years ago, the average age of Ramesh and Aadil was 40 years.

The present age of Ramesh, Aadil and John is 60 years.

**Formula Used****∶**

Concept of average, Average = Sum of observations/ Number of Observations

**Calculation****∶**

Let the present age of Ramesh, Aadil and john be a, b and c years respectively.

20 years ago, Ramesh age = (a – 20) years

Aadil age = (b – 20) years

According to question,

[(a – 20) + (b – 20)]/2 = 40

⇒ a + b – 40 = 80

⇒ a + b = 120 ----(1)

Now, Average of present ages of Ramesh, Aadil and John = 60

So, (a + b + c)/3 = 60

⇒ (a + b + c) = 180 ----(2)

Put the value of a + b = 120 from eq (1) in eq. (2), we get

120 + c = 180

⇒ c = 180 – 120 = 60

John’s present age = c = 60 years

After 7 years,

John age = 60 + 7 = 67 years

**Hence, the age of John after 7 years is 67 years.**