1. **State the problem:** Find the area of the composite figure consisting of a rectangle and a trapezoid on top.
2. **Identify dimensions:**
- Rectangle: width = 18 ft, height = 12 ft
- Trapezoid: top base = 10 ft, height = 6 ft, right angle on the left side means the trapezoid has one vertical leg.
3. **Formula for area:**
- Rectangle area = width \times height
- Trapezoid area = \frac{(b_1 + b_2)}{2} \times h, where $b_1$ and $b_2$ are the two bases and $h$ is the height.
4. **Find trapezoid bases:**
- Bottom base of trapezoid = width of rectangle = 18 ft
- Top base of trapezoid = 10 ft
5. **Calculate areas:**
- Rectangle area = $18 \times 12 = 216$ ft$^2$
- Trapezoid area = $\frac{(10 + 18)}{2} \times 6 = \frac{28}{2} \times 6 = 14 \times 6 = 84$ ft$^2$
6. **Sum areas for total area:**
$$\text{Total area} = 216 + 84 = 300 \text{ ft}^2$$
**Final answer:** The area of the figure is **300 ft$^2$**.
Composite Area Dabbc9
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