Remember all those times in grade school when you were like, “Ugh, I hate math and I am never going to use it when I’m older! Never!”? Well if you enjoy drinking hard cider and would rather not be paying a higher price just to get it in a bigger glass, those math skills you insisted you’d never need would come in handy right about now.

Consumerist reader Bob sent us a link to a photo he took at a watering hole, advertising what one would assume to be a good deal upon first glance.

I saw this sign yesterday at a local sports bar. It makes you think you are getting a price break by buying the larger size when in reality it is more expensive per ounce.

Let’s break this down, shall we? At $3.00 for 16 ounces of cider, you’d be paying about $0.19 per ounce. But if you need a whopping 23 ounces right away you can shell out $5.00 — which comes out to about $0.22 per ounce. Basically, you’re paying more per ounce for the privilege of a larger cup.

Remember that just because a sign has prices listed on it, it’s not necessarily a good deal. And if you still hate math, you can still bust out your calculators or calculator apps. It might just be worth your while to crunch the numbers.

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