To determine which of the following options represents a rational number, let's evaluate each square root:

A. $\sqrt{3}$

• $\sqrt{3}$ is an irrational number since 3 is not a perfect square.

B. $\sqrt{\pi}$

• $\pi$ is an irrational number, and taking the square root of an irrational number will also be irrational.

C. $\sqrt{8}$

• $\sqrt{8}$ can be simplified as $\sqrt{4 \times 2} = 2\sqrt{2}$. Since $\sqrt{2}$ is irrational, this is irrational.

D. $\sqrt{\frac{3}{18}}$

• Simplifying the fraction: $\frac{3}{18} = \frac{1}{6}$, so $\sqrt{\frac{1}{6}}$ is irrational because $\sqrt{6}$ is irrational.

E. $\sqrt{\frac{25}{36}}$

• This simplifies to $\frac{\sqrt{25}}{\sqrt{36}} = \frac{5}{6}$, which is a rational number.

Conclusion:

The correct answer is E $\sqrt{\frac{25}{36}}$, since it simplifies to $\frac{5}{6}$, a rational number.

Would you like more details on these calculations, or do you have any questions?

Here are five related questions you might want to explore:

1. What is the definition of a rational number?
2. Can all square roots be simplified to rational numbers?
3. Why is $\sqrt{2}$ considered irrational?
4. How do we simplify square roots of fractions?
5. What is the difference between rational and irrational numbers?

Tip: A rational number can always be expressed as a ratio of two integers, like $\frac{5}{6}$.