Mathematics and advertising

I occasionally post here about abuse of mathematics (such as this post, and this one, and this one). I occasionally post about silly advertising (try here and here). And sometimes I get to combine them in an item about abuse of mathematics in advertising (this is a good example).

The other day, the excellent web comic XKCD covered the combo very nicely, and included some of the things I often whine get huffy kvetch whine and get huffy about:

Hold the mouse over the comic to see Randall Munroe’s extra text, present in most of his drawings. Click the comic to visit his web page. And while you’re at it, you might check out my other favourite XKCD comics: Sandwich (it’s a Unix joke), Snopes, Correlation, Can’t Sleep (warning: only extreme geeks will get this), and Spinal Tap Amps.