Pi Day Math for Cooks

First of all – Happy Pi Day!
If you are a math nerd, this is a fun day!
March 14 or 3.14…and I did not just admit to being a nerd?!?

What is pi?
It is the ratio of the circle’s circumference to its diameter.

So here, my lovely Le Creuset Enameled Cast-Iron Tarte Tatin pan has a diameter of 9 1/2 inches. What is the circumference you ask?
That is where my handy little mysterious irrational number comes in! The circumference is the diameter (as measured by my whimsical tape measure) multiplied by pi.
The circumference of my Le Creuset pan:
pi d = C
3.141592653589793238462643383279502884+ X 9.5 = 29.845130209+
About 30″ around.
OK, I am off to bake a 30″ circumference apple tarte tatin!
Did you enjoy some pie on Pi Day?

(Portions of this post were written for Pi Day 2008, as some things never change, and pi is one of them).