1. **State the problem:** Find the area of the base of the composite figure consisting of a triangle and a parallelogram. 2. **Identify the shapes and dimensions:** - Triangle with base $12\text{ cm}$ and height $8\text{ cm}$. - Parallelogram with base $15\text{ cm}$ and height $10\text{ cm}$. 3. **Formulas:** - Area of triangle: $$\text{Area} = \frac{1}{2} \times \text{base} \times \text{height}$$ - Area of parallelogram: $$\text{Area} = \text{base} \times \text{height}$$ 4. **Calculate the area of the triangle:** $$\text{Area}_{\triangle} = \frac{1}{2} \times 12 \times 8 = \frac{1}{2} \times 96 = 48$$ 5. **Calculate the area of the parallelogram:** $$\text{Area}_{\text{parallelogram}} = 15 \times 10 = 150$$ 6. **Calculate the total area of the base:** $$\text{Total area} = 48 + 150 = 198$$ 7. **Write the final answer with units:** The area of the base is **198.00 cm^2**.