1. The problem is to simplify the expression $$\frac{(40 - a)^5}{a^5}$$. 2. We use the property of exponents that states $$\frac{x^m}{y^m} = \left(\frac{x}{y}\right)^m$$. 3. Applying this property, we rewrite the expression as $$\left(\frac{40 - a}{a}\right)^5$$. 4. This is the simplified form of the given expression. Therefore, the final answer is $$\left(\frac{40 - a}{a}\right)^5$$.