Pi Day Explained - Sort of

Last March 14, I happened to walk past my local pie shop and there was a line out the door. That's quite a rarity for my little local shop, so I rummaged through my mind and determined that it wasn't Valentine's Day, or Sweetheart's Day, or Mother's Day. I just didn't know why so many people were queueing up for strawberry rhubarb pie, so I asked someone who was standing in line. "What's the occasion?", I said. She looked at me with a sneer, plainly implying I was an idiot, and spat out, "Pi Day".

Happy Pi Day Tshirt

Okay, so I'm not a geek, a nerd, a math major or even very good at calculus. But she had succeeded in making me feel a little bit dumb. Of course, Pi Day has to fall on March 14, doesn't it?

Pi Day Cartoon Humor Pi is a mathematical term we all learned about in school. For my part, I remember that finding the volume of a circle - or is it the square root of a cylinder? - has something to do with pi. It was one of those "I'll never use this information in a million years" moments that I had so many of in math class. And I can proudly say that so far, I've been correct. Still, some people might find it useful to know these pi facts I got off the internet:

Peace of the Pi tshirt

* Pi is infinite. Unlike my local pie shop which can only turn out a couple hundred pies a day, the number Pi never ends. Not sure if that means it isn't really a number, or not. But the fact remains, according to this reddit page, "because we know that if a number repeats it must be rational and because pi is irrational it can not repeat. As someone else pointed out we know that any finite number can be written as the ratio of two integers easily so as a consequence we know that since Pi is not rational then it must be infinite." OK, whatever.

* If you got that, you know now that Pi is irrational. My grandmother was irrational, too, which is a definition I understand. But I had to go to a kids' website to understand what an irrational number is. According to Mathisfun.com , an irrational number is "a real number that cannot be written as a simple fraction." I guess that's why Pi has to have its own little symbol, which looks like a tiny little gate to hell:

* Congress, in early 2009, passed a bipartisan resolution designating March 14th of each year as "Pi Day." This may be the last thing Congress ever agreed on.

* By definition, pi is the ratio of the circumference of a circle to its diameter. Pi is always the same number, no matter which circle you use to compute it.

* So far, pi has been calculated up to more than a trillion digits.

* Here's a weird one: the first 144 digits of pi add up to 666!!

* In The Wizard of Oz, the Scarecrow, after he gets his brain, does not talk about pi. This is something I had wrong for centuries! Turns out he was quoting the Pythagorean Theorem (although apparently he gets it wrong).

So there you have it! Now you understand Pi as well as I do. Which is to say, I still don't get it. But if you see me standing in line at the pie store, please say hello anyway.