1. **State the problem:** We are given the second term of a geometric progression (GP) as 5, and we need to find the product of the first three terms. 2. **Recall the formula for terms of a GP:** The $n$-th term of a GP is given by $$a_n = ar^{n-1}$$ where $a$ is the first term and $r$ is the common ratio. 3. **Express the given information:** The second term is $$a_2 = ar = 5$$ 4. **Write the first three terms:** - First term: $a$ - Second term: $ar = 5$ - Third term: $ar^2$ 5. **Find the product of the first three terms:** $$P = a \times ar \times ar^2 = a^3 r^3$$ 6. **Rewrite the product using $a_2$:** Since $ar = 5$, then $$a^3 r^3 = (ar)^3 = 5^3 = 125$$ 7. **Final answer:** The product of the first three terms of the GP is $$\boxed{125}$$