If you multiply the two digits corresponding to my age, you get half of the years I am.

**How old am I?**

#### Solution

**I `m 36 years old.** 3 × 6 = 18 which is half of 36. From the statement we can deduce the following equation:

X × 10 + Y = 2 × X × Y

If we clear for example * X*, where we get that Y = 2XY - 10X = X (2Y-10) from where we deduce that X = Y / (2Y-10)

If we look for all the whole solutions of

*and*

**X***where each*

**Y***and every*

**X***be composed of a single digit we find that there is only one: X = 3 and Y = 6*

**Y**