1. **State the problem:**
We have a sector with a central angle of 60° and an unknown radius $r$. Its area equals the area of a circle with radius 7 cm.
2. **Formulas:**
- Area of a sector: $$A_{sector} = \frac{\theta}{360} \times \pi r^2$$ where $\theta$ is the central angle in degrees.
- Area of a circle: $$A_{circle} = \pi R^2$$ where $R$ is the radius of the circle.
3. **Given:**
- $\theta = 60^\circ$
- $R = 7$ cm
- $\pi = \frac{22}{7}$
4. **Set the areas equal:**
$$\frac{60}{360} \times \pi r^2 = \pi \times 7^2$$
5. **Simplify the fraction:**
$$\frac{60}{360} = \frac{1}{6}$$
6. **Substitute and simplify:**
$$\frac{1}{6} \times \pi r^2 = \pi \times 49$$
7. **Divide both sides by $\pi$:**
$$\cancel{\pi} \times \frac{1}{6} r^2 = \cancel{\pi} \times 49 \implies \frac{1}{6} r^2 = 49$$
8. **Multiply both sides by 6:**
$$r^2 = 49 \times 6 = 294$$
9. **Find $r$ by taking the square root:**
$$r = \sqrt{294}$$
10. **Simplify $\sqrt{294}$:**
$$294 = 49 \times 6$$
$$r = \sqrt{49 \times 6} = \sqrt{49} \times \sqrt{6} = 7 \sqrt{6}$$
**Final answer:**
The radius of the sector is $$r = 7 \sqrt{6} \text{ cm}$$.
Sector Radius Bd1780
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