Real Pizza is offering a student sale on its world-famous pizza! For the same price of $12.99, you can choose either option A or option B (see below).

a. 2 Medium Pizzas (12" diameter). Each medium pizza has 6 slices.

b. 1 Large Pizza (18" diameter). Each large pizza has 12 slices.

Which pizza offer is the best deal? Use what you know about circles to select an answer. Computational work must be shown to receive full credit.

1 answer

To determine which pizza option offers the best deal, we need to calculate the total area of each option since the price is the same for both. The pizza with a larger total area will provide more pizza at the same price.

The area \( A \) of a circle is calculated using the formula:

\[ A = \pi r^2 \]

where \( r \) is the radius of the circle.

Option A: 2 Medium Pizzas (12" diameter)

  1. Calculate the radius of a medium pizza:

    • Diameter = 12 inches
    • Radius \( r = \frac{Diameter}{2} = \frac{12}{2} = 6 \) inches
  2. Calculate the area of one medium pizza:

\[ A_{medium} = \pi (6^2) = \pi (36) \approx 113.10 \text{ square inches} \]

  1. Calculate the total area for 2 medium pizzas:

\[ A_{total, medium} = 2 \times A_{medium} = 2 \times 113.10 \approx 226.20 \text{ square inches} \]

Option B: 1 Large Pizza (18" diameter)

  1. Calculate the radius of a large pizza:

    • Diameter = 18 inches
    • Radius \( r = \frac{Diameter}{2} = \frac{18}{2} = 9 \) inches
  2. Calculate the area of the large pizza:

\[ A_{large} = \pi (9^2) = \pi (81) \approx 254.47 \text{ square inches} \]

Conclusion

  • Total area for 2 medium pizzas: \( \approx 226.20 \text{ square inches} \)
  • Total area for 1 large pizza: \( \approx 254.47 \text{ square inches} \)

Since \( 254.47 \) square inches (option B) is greater than \( 226.20 \) square inches (option A), Option B (1 Large Pizza) provides the best deal in terms of pizza area for the price.