1. **Problem Statement:** Find the total area of the shaded portions of two semicircles, each with diameter 42 cm. 2. **Formula for the area of a semicircle:** $$\text{Area} = \frac{1}{2} \pi r^2$$ where $r$ is the radius of the semicircle. 3. **Calculate the radius:** Given diameter $d = 42$ cm, radius $r = \frac{d}{2} = \frac{42}{2} = 21$ cm. 4. **Calculate the area of one semicircle:** $$\text{Area} = \frac{1}{2} \times \frac{22}{7} \times 21^2 = \frac{1}{2} \times \frac{22}{7} \times 441$$ 5. **Simplify the calculation:** $$= \frac{1}{2} \times 22 \times 63 = 11 \times 63 = 693 \text{ cm}^2$$ 6. **Calculate the total shaded area (two semicircles):** $$2 \times 693 = 1386 \text{ cm}^2$$ **Final answer:** The total shaded area of the two semicircles is $1386$ cm$^2$.