A 7 inch pizza cost $8 and a 14 inch pizza costs $20. Tommy says the smaller pizza is a better buy because the larger pizza is twice as big and more than twice as expensive. Do you agree with his reasoning? Explain why or why not.

Area of 7 inch pizza:

A = pi * r^2
A = 3.14 * 3.5 * 3.5
A = 38.465 square inches

8/38.465 = $0.21 per square inch

Follow the above procedure to find the area and cost per square inch of the larger pizza.

A = pi x r^2

A = 3.14 x 7 x7
A = 153.86
20/153.86 = $0.13 per square inch

Right! :-)

Thank you!

You're welcome.

To determine whether Tommy's reasoning is correct, we need to compare the price per square inch of the two pizza sizes.

First, let's calculate the area of each pizza:
- The area of a 7-inch pizza is π * (7/2)^2 = 38.48 square inches.
- The area of a 14-inch pizza is π * (14/2)^2 = 153.94 square inches.

Next, we can calculate the price per square inch for each pizza:
- For the 7-inch pizza, $8 ÷ 38.48 square inches = $0.21 per square inch.
- For the 14-inch pizza, $20 ÷ 153.94 square inches = $0.13 per square inch.

Based on these calculations, we can see that the 14-inch pizza actually has a lower price per square inch ($0.13) compared to the 7-inch pizza ($0.21). Therefore, Tommy's reasoning is incorrect. Though the 14-inch pizza is more expensive, it is actually a better buy in terms of price per square inch.