1. **State the problem:** We need to find the surface area of a triangular pyramid composed of six triangular faces, with three top triangles each having height 11 ft and three bottom triangles with sides 7 ft and height 6.1 ft.
2. **Identify the triangles:** The pyramid has 6 triangular faces: 3 top triangles with height 11 ft and base 7 ft, and 3 bottom triangles with base 7 ft and height 6.1 ft.
3. **Formula for the area of a triangle:**
$$\text{Area} = \frac{1}{2} \times \text{base} \times \text{height}$$
4. **Calculate the area of one top triangle:**
$$\text{Area}_{top} = \frac{1}{2} \times 7 \times 11 = \frac{1}{2} \times 77 = 38.5$$
5. **Calculate the area of one bottom triangle:**
$$\text{Area}_{bottom} = \frac{1}{2} \times 7 \times 6.1 = \frac{1}{2} \times 42.7 = 21.35$$
6. **Calculate total surface area:**
$$\text{Total area} = 3 \times 38.5 + 3 \times 21.35 = 115.5 + 64.05 = 179.55$$
7. **Final answer:** The surface area of the triangular pyramid is
$$179.55\ \text{ft}^2$$
Triangular Pyramid Area Dc954C
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