It's National Pi Day today – 3/14, which coincides with the first few digits of that well-known math number 3.14. And math nerds around the country are celebrating.
You may remember from math class that pi (represented by the Greek letter "π") is the ratio of a circle's circumference to its diameter, commonly approximated as 3.14159. It's true for any circle of any size.
Because it's an irrational number, pi is infinite and never falls into a repeating pattern.
This year, it's actually more of a Super Pi Day – the first perfect Pi Day in a century, because the first five digits of pi are the same as the digits of the day's date: 3/14/15, or 3.1415.
What's more, we'll see pi extend to nine digits Saturday evening, at 9:26:53 p.m. – 3.141592653 (of course, it also occurred at 9:26 a.m.)
March 14 was designated Pi Day by Congress in 2009, in part as a way to encourage more people to get involved in math and science activities.
Even country music star Keith Urban got into the act with this video he posted on his Twitter feed.
Even non-math nerds are celebrating - mostly by eating pie or talking about eating pie. Bakeries and restaurants are taking advantage of the attention by offering special deals on pie – the dessert variety and the pizza variety.
It's best to heed this warning, though.
So, besides those of us who study math, why does pi matter? The New Yorker explains all.
And here's a video which explains pi in 3 minutes and 14 seconds. Enjoy!
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