If you ever eat pizza, always get the biggest size possible – at least according to this study. The chart above, generated from 74,476 pizza prices by 3,578 American pizza places, shows that as the pizza gets bigger, the price per square inch becomes cheaper.

And the reason is simple. It all boils down to math:  a 16-inch pizza is actually four times larger than an 8-inch one, not twice (which is what most people intuitively think it is).

Of course, the study assumes you’re going to finish what you ordered. And if you can only stomach so many slices, you should get the smaller one. Or do what I do: pack it up and eat it again in the office.