The problem asks which of the following numbers is farthest from 2 on the number line:

1. $\sqrt{2.1}$
2. $\sqrt{2.4}$
3. $\sqrt{2.5}$
4. $\sqrt{2.9}$

To solve this, let's first approximate the square roots and then determine which is farthest from 2.

1. $\sqrt{2.1} \approx 1.449$
2. $\sqrt{2.4} \approx 1.549$
3. $\sqrt{2.5} \approx 1.581$
4. $\sqrt{2.9} \approx 1.702$

Now, find the distances from 2:

• $|2 - 1.449| \approx 0.551$
• $|2 - 1.549| \approx 0.451$
• $|2 - 1.581| \approx 0.419$
• $|2 - 1.702| \approx 0.298$

The number farthest from 2 is $\sqrt{2.1}$, as its distance from 2 is the largest at approximately 0.551.

Would you like more details, or have any questions?

Here are 5 related questions:

1. What is the square root of 3 to two decimal places?
2. How can we approximate square roots without a calculator?
3. What is the significance of distance on the number line in math?
4. How is absolute value used in measuring distances on a number line?
5. Why are square roots of non-perfect squares irrational?

Tip: When calculating square roots mentally, try using nearby perfect squares to estimate values.