### Home > MC2 > Chapter 6 > Lesson 6.2.5 > Problem 6-118

6-118.

To find the best cost per square inch, we must first find the area of each pizza.

Using the formula for the area of a circle, *r*^{2}π:

Medium pizza: 6^{2}π = 36π = 113.04 in^{2}.

Large pizza: 9^{2}π = 81π = 254.34 in^{2}.

Remember, 12 in. and 18 in. are the diameters of the pizzas.

Now with the area, we can determine the price per square inch of pizza. We can convert to cents for a better indicator of price.

Medium pizza: $10 = 1000 cents

Large pizza: $16 = 1600 cents