A father tells his son, "I was of your present age when you were born." If the father is now 36 years of age, how old was the boy 5 years ago?

Correct option is A

The father's statement sets their age difference equal to the son's current age. Solving it gives the son's age as 18, and 5 years ago, he was 13.

We are given:

• Father says: "I was of your present age when you were born."

• Father’s current age = 36 years

Let’s solve it step by step.

Step 1: Let son’s present age be x

Then, when the son was born, father’s age = x
So, at that time, father's age = x and son's age = 0
Therefore, the age difference between father and son = 36 - x

This same difference must be maintained throughout their lives.

So:

Father's current age – Son's current age = 36 – x = x
=> 36 = 2x
=> x = 18

Step 2: Son's age 5 years ago = 18 – 5 = 13

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