1. **State the problem:** We need to find the weighted average of points A, B, and C on a number line where point B weighs twice as much as point A, and point C weighs twice as much as point A.
2. **Identify the points and weights:**
- Point A is at $-5$ with weight $w_A = 1$ (let's assign this as the base weight).
- Point B is at $-4$ with weight $w_B = 2 \times w_A = 2$.
- Point C is at $2$ with weight $w_C = 2 \times w_A = 2$.
3. **Formula for weighted average:**
$$\text{Weighted Average} = \frac{w_A x_A + w_B x_B + w_C x_C}{w_A + w_B + w_C}$$
4. **Substitute values:**
$$= \frac{1 \times (-5) + 2 \times (-4) + 2 \times 2}{1 + 2 + 2}$$
5. **Calculate numerator:**
$$= \frac{-5 - 8 + 4}{5}$$
6. **Simplify numerator:**
$$= \frac{-9}{5}$$
7. **Calculate weighted average:**
$$= -1.8$$
**Final answer:** The weighted average of points A, B, and C is $-1.8$.
Weighted Average A5E3Bb
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