Ricky's Pizza Parlor has three different sizes of pizza: a large (15 in. round), a medium (13 in round), and a small (10 in. round). A single-topping large pizza sells for $18. A single-topic medium pizza sells for $15 and a single-topping small pizza sells for $12. Which pizza is the best buy?
Find the area of each pizza.
A = pi * r^2
Divide the price by the area of each one to find the best buy.
To determine which pizza is the best buy, we need to compare the prices relative to the size of each pizza. We can calculate the price per square inch of pizza for each size and compare the values to determine the best buy.
First, let's calculate the area of each pizza:
- The large pizza has a radius of 15 / 2 = 7.5 inches. The area of a circle is calculated by using the formula A = π * r^2, where A is the area and r is the radius. So, the area of the large pizza is approximately 3.14 * (7.5)^2 = 176.625 square inches.
- The medium pizza has a radius of 13 / 2 = 6.5 inches. Using the same formula, the area of the medium pizza is approximately 3.14 * (6.5)^2 = 132.665 square inches.
- The small pizza has a radius of 10 / 2 = 5 inches. Again, using the formula, the area of the small pizza is approximately 3.14 * (5)^2 = 78.5 square inches.
Now, let's calculate the price per square inch for each pizza:
- The large pizza costs $18 with an area of 176.625 square inches. Therefore, the price per square inch of the large pizza is $18 / 176.625 = $0.1019.
- The medium pizza costs $15 with an area of 132.665 square inches. Therefore, the price per square inch of the medium pizza is $15 / 132.665 = $0.1132.
- The small pizza costs $12 with an area of 78.5 square inches. Therefore, the price per square inch of the small pizza is $12 / 78.5 = $0.1529.
Comparing the price per square inch, we can see that the large pizza has the lowest value ($0.1019) and is the best buy among the three sizes.