At some point in your life you will be asked to order pizza for a group. When that time comes, don’t be afraid. All the information you need to determine how many pies to order can be found in the pizza itself. Because what is a pizza if not a tool for learning fractions?

Typically, pizzas are cut into eight slices, making each slice one-eighth of a pizza. If a hungry person can eat three slices of pizza, and each pizza has eight slices, how many pies should you order for your group? The answer is

X * ⅜ = P



where X is the number of guests, and P is the number of pies you should order. If you are seeing this after you ordered, you can also move the variables around and solve for X to figure out how many people are going to go hungry because you used your brain instead of the Pizza Equation.

It’s important to note that no two pizzas are alike. If you are opting for thin crust, round P up to the nearest pie. For deep dish or smaller appetites, round down. There are other variables at play, like the diameter of the pizza and the number toppings. But ordering pizza is supposed to be simple. Don’t complicate it by asking a bunch questions in the middle of a party. Just enter the number of guests you need to feed above, and let the widget do the math.

[Pizza photo via Shutterstock]

Julia Alvidrez is Project Manager, Construction and Planning at Gawker Media.