1. **State the problem:** Determine which pizza is the better buy by comparing the unit price per square inch for each pizza. 2. **Formula for area of a circle:** $$A = \pi r^2$$ where $r$ is the radius of the pizza. 3. **Calculate the area of the 10-inch diameter pizza:** - Radius $r = \frac{10}{2} = 5$ inches - Area $A = 3.14 \times 5^2 = 3.14 \times 25 = 78.5$ square inches 4. **Calculate the unit price of the 10-inch pizza:** - Price = 8.99 - Unit price $= \frac{8.99}{78.5} \approx 0.1146$ per square inch 5. **Calculate the area of the 6-inch diameter pizza:** - Radius $r = \frac{6}{2} = 3$ inches - Area $A = 3.14 \times 3^2 = 3.14 \times 9 = 28.26$ square inches 6. **Calculate the unit price of the 6-inch pizza:** - Price = 5 - Unit price $= \frac{5}{28.26} \approx 0.177$ per square inch 7. **Compare the two unit prices:** - 10-inch pizza unit price $\approx 0.1146$ - 6-inch pizza unit price $\approx 0.177$ - The 10-inch pizza is the better buy because it has a lower unit price. 8. **Calculate the area of the 4-inch radius pizza:** - Area $A = 3.14 \times 4^2 = 3.14 \times 16 = 50.24$ square inches 9. **Calculate the unit price of the 4-inch radius pizza:** - Price = 3 - Unit price $= \frac{3}{50.24} \approx 0.0597$ per square inch 10. **Calculate the area of the 8-inch radius pizza:** - Area $A = 3.14 \times 8^2 = 3.14 \times 64 = 200.96$ square inches 11. **Calculate the unit price of the 8-inch radius pizza:** - Price = 14 - Unit price $= \frac{14}{200.96} \approx 0.0697$ per square inch 12. **Compare the two unit prices:** - 4-inch radius pizza unit price $\approx 0.0597$ - 8-inch radius pizza unit price $\approx 0.0697$ - The 4-inch radius pizza is the better buy because it has a lower unit price. **Final answers:** - Better buy between 10-inch and 6-inch diameter pizzas: **10-inch pizza** - Better buy between 4-inch and 8-inch radius pizzas: **4-inch radius pizza**