1. **State the problem:** Find the surface area of a composite solid made of two rectangular prisms joined together.
2. **Identify dimensions:**
- Prism 1: $13 \text{ cm} \times 7 \text{ cm} \times 5 \text{ cm}$
- Prism 2: $5 \text{ cm} \times 5 \text{ cm} \times 2 \text{ cm}$
3. **Formula for surface area of a rectangular prism:**
$$SA = 2(lw + lh + wh)$$
where $l$, $w$, and $h$ are the length, width, and height.
4. **Calculate surface area of Prism 1:**
$$SA_1 = 2(13 \times 7 + 13 \times 5 + 7 \times 5)$$
$$= 2(91 + 65 + 35) = 2(191) = 382 \text{ cm}^2$$
5. **Calculate surface area of Prism 2:**
$$SA_2 = 2(5 \times 5 + 5 \times 2 + 5 \times 2)$$
$$= 2(25 + 10 + 10) = 2(45) = 90 \text{ cm}^2$$
6. **Calculate the area of the overlapping face:**
The two prisms are joined along a face of size $5 \text{ cm} \times 5 \text{ cm}$.
$$A_{overlap} = 5 \times 5 = 25 \text{ cm}^2$$
7. **Calculate total surface area of the composite solid:**
$$SA = SA_1 + SA_2 - 2 \times A_{overlap}$$
We subtract twice the overlapping area because it is counted in both prisms' surface areas but is not exposed.
$$SA = 382 + 90 - 2 \times 25 = 472 - 50 = 422 \text{ cm}^2$$
**Final answer:**
$$\boxed{422 \text{ cm}^2}$$
Surface Area Composite F4F73D
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