To solve for $FG$ on the number line:

1. First, identify the positions of points $F$ and $G$ on the number line:

   • Point $F$ is at $-1$.
   • Point $G$ is at $3$.

2. To find the distance $FG$, subtract the coordinate of $F$ from that of $G$: $FG = |3 - (-1)| = |3 + 1| = |4| = 4$

Thus, the distance between $F$ and $G$ is $4$.

However, none of the options exactly match 4, but option D (4.5) is the closest.

Would you like any further details or clarifications?

Here are 5 related questions for you to consider:

1. How would you find the distance between two negative points on the number line?
2. What is the relationship between absolute value and distance on the number line?
3. Can the distance between two points on the number line ever be negative?
4. How does finding the distance between two points differ in 2D versus 1D (like this number line)?
5. What does it mean if the coordinates of two points are the same?

Tip: Always take the absolute value when calculating distance on a number line to ensure the result is non-negative.