Question: Simplify the expression.
$\left(\frac{x}{3}\right)^3$
$x$
[?]
1. **State the problem:** Simplify the expression $$\left(\frac{x}{3}\right)^3$$.
2. **Recall the power of a quotient rule:** $\left(\frac{a}{b}\right)^n = \frac{a^n}{b^n}$.
3. **Apply the rule:**
$$\left(\frac{x}{3}\right)^3 = \frac{x^3}{3^3}$$
4. **Calculate the denominator:**
$$3^3 = 27$$
5. **Write the simplified expression:**
$$\frac{x^3}{27}$$
6. **Final answer:**
$$\boxed{\frac{x^3}{27}}$$