If you've ever stood at the grocery store trying to figure out if it was a better deal to buy two smaller pizzas or one larger pizza, this story is for you. What happens when a personal finance blogger gets offered two 8" pizzas instead of one 12"? Geometry! From The Binary Dollar:

After doing some quick mental math (area of a circle = pi*radius . Two 8 pizzas = 2*pi*(4) = 32*pi square inches, One 12 pizza = pi*(6) = 36*pi square inches), I told her we'd be missing out on over 12 square inches of pizza, so we'd rather just have the one 12 pizza. She complied, and as a nice bonus (probably because she was impressed by my quick geometry skills), she let us have the extra 8 pizza anyways. Score one for geometry!

Geometry Saved Me Money [Binary Dollar]
(Photo: Dustin P. Smith)