Given that the Highest Common Factor (HCF) of two numbers is 12 and their sum is 72, we need to find the two numbers.

Let's denote the two numbers by $a$ and $b$.

We know: $\text{HCF}(a, b) = 12 \quad \text{and} \quad a + b = 72$

Since the HCF is 12, we can express the numbers $a$ and $b$ as: $a = 12m \quad \text{and} \quad b = 12n$ where $m$ and $n$ are integers that are coprime (i.e., their HCF is 1).

Substituting into the sum equation: $12m + 12n = 72$ Simplifying this equation, we get: [ m + n =