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Pizza Rule
(telegra.ph)
Be sure to follow the rule before you head out.
Rule: You must post before you leave.
This is why, if you order pizza, getting anything less that the absolute largest size they offer is throwing your money away. Leftover pizza is great.
The math only really works for 18+ inch pizzas though. The pizza places around me don't even offer 18 inch pizzas. 14" large or 16" XL are the highest they go. In that case at most places near me, two twelves is often cheaper per square inch and does have more area than one 14" or 16". Especially since Domino's usually has coupons for two 12s that make it significantly cheaper than 1 L or XL.
Pizza place that just opened up down the street from me only offers one size:
18 inches.
The other option is to purchase by the slice.