Chapter 1 - Measurement and Problem Solving - Learning Path Questions and Exercises - Exercises - Page 31: 64

Area of outer ring is bigger.

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.