The expression $3\sqrt{54}$ can be simplified as follows:

1. Break down the square root: $\sqrt{54} = \sqrt{9 \times 6} = \sqrt{9} \times \sqrt{6} = 3\sqrt{6}$

2. Multiply by the 3 outside the square root: $3\sqrt{54} = 3 \times 3\sqrt{6} = 9\sqrt{6}$

So, the simplified form of $3\sqrt{54}$ is $9\sqrt{6}$.

Would you like more details on this simplification process?

Here are 5 related questions to explore:

1. How do you simplify square roots with prime factors?
2. What are other ways to express square roots with non-perfect squares?
3. How do you add or subtract expressions with square roots?
4. How do you multiply and divide expressions involving square roots?
5. What are some real-world applications of simplifying radicals?

Tip: When simplifying square roots, always look for perfect square factors to make the process easier.