1. **Problem statement:** Find the sum of the interior angles of a pentagon. 2. **Formula:** The sum of interior angles of a polygon with $n$ sides is given by: $$\text{Sum} = (n - 2) \times 180^\circ$$ 3. **Apply the formula:** For a pentagon, $n = 5$. $$\text{Sum} = (5 - 2) \times 180^\circ = 3 \times 180^\circ$$ 4. **Calculate:** $$3 \times 180^\circ = 540^\circ$$ 5. **Explanation:** A pentagon has 5 sides, and the sum of its interior angles is always 540 degrees. This is because any polygon can be divided into triangles, and each triangle's interior angles sum to 180 degrees. For a pentagon, it can be divided into 3 triangles. **Final answer:** 540°