1. **State the problem:** Find the distance between the points $(9.4, 10)$ and $(9.4, 6)$. 2. **Formula used:** The distance $d$ between two points $(x_1, y_1)$ and $(x_2, y_2)$ is given by the distance formula: $$d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}$$ 3. **Apply the formula:** Since the points have the same $x$-coordinate, the distance is simply the difference in the $y$-coordinates: $$d = \sqrt{(9.4 - 9.4)^2 + (6 - 10)^2}$$ 4. **Simplify inside the square root:** $$d = \sqrt{0^2 + (-4)^2} = \sqrt{16}$$ 5. **Calculate the square root:** $$d = 4$$ 6. **Interpretation:** The distance between the points is 4 units.