​Sanjay is 25 years older than his son and Sanjay's wife is 65 years old. If the average age of all the three members of this family is 58 years, then find the age of the son.

Correct option is D

​Given:

Let Son's Age = x

Sanjay's age = S = x + 25.

Wife's age = 65

Average age = 58

Formula Used:

​$$\text{Sum of ages} = 3 \times \text{Average age}$$​​

Solution: 

Now, 

According to the question;

​$$x + (x + 25) + 65 = 3 \times 58$$​

​$$2x + 90 = 174 \\ \ \\ 2x = 84 \\ \ \\ \implies x = 42$$ 

Thus, The age of the Son is 42 years.