Here’s a good one.

We ordered pizza the other day for Kyra’s birthday, and had a coupon for a one-topping medium pizza for five bucks (limit three). Laralee placed the order: one medium pepperoni, one medium mushroom, one medium cheese.

I went to pick up the pizzas, showed them my coupon, and the total rang up to $18.50 or something. I made a comment that $3.50 was a lot of tax considering the order total was $15.00, and the woman seemed surprised.

Her: Well, the coupon is only good for one-topping pizzas.
Me: Yes. And I have three one-topping pizzas.
Her: No, this is just two.
Me: No, pepperoni is one topping; so is mushroom and so is cheese.
Her: Actually, cheese comes with the pizzas, so it doesn’t count as a topping.

(pregnant pause)

Me: So you’re saying that’s a zero-topping pizza?
Her: That’s right. And it costs $7.99.

(me thinking)

Me: Can I get extra cheese? Would that count as a one-topping pizza?
Her: Absolutely.
Me: And then the pizza would cost five dollars, like the coupon says?
Her: Yes.
Me: Umm, okay, could you sprinkle on some extra cheese then?

So she did, and my total dropped to $14.30. I still couldn’t figure out the math (maybe the tax was negative?) but I’d saved four bucks by adding a topping, so I didn’t complain.