After 12 years I shall be 3 times as old as I was 4 years ago. Find my present age.

Explanation

To solve the problem step by step, we can follow these instructions:

### Step 1: Define the Present Age
Let the present age be represented by \( X \).

### Step 2: Express Future Age
According to the problem, after 12 years, the age will be:
\[
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