## College Physics (7th Edition)

Area of inner circle = $\frac{22}{7} \times Radius^{2}=\frac{22}{7} \times 0.64^{2} cm^{2}=1.29cm^{2}$ Area of outer ring = $\frac{22}{7} \times (1.78^{2}-1.66^{2})=1.297cm^{2}$ So, area of outer ring is bigger.