According to our March math activity calendar, the tastiest of all math holidays is coming up on March 14: **National Pi Day**! Let’s have some fun and share our favorite pie. Comment below with your favorite pie flavor. I don’t know about you, but I can’t decide between French Silk or Key Lime. Maybe I’ll just invent a Key Lime-French Silk combo pie. Florida meets France in a delicious graham cracker crust… hungry yet?

Chow down on your favorite pie (after you measure its diameter, of course). And while you savor your dessert, read our 14 delicious facts about Pi.

## 14 delicious facts about Pi

- Pi is the number of times a circle’s diameter will fit around its circumference
- There is no zero in the first 31 digits of Pi
- Pi has 6.4 billion known digits – it would take a person approximately 133 years to recite all of them without stopping
- At position 763 (known as Feynman Point), there are six nines in a row
- Some people believe Pi contains the answers of the universe. (But on some days, a
*slice*of pie holds all the answers to the universe!) - It took nine hours for the Memorized-Digits-of -Pi world record holder to recite over 44,000 digits
- Pi Day (March 14) is also Albert Einstein’s birthday!
- Pi is irrational — no, not like my mother. An irrational number is one that cannot be expressed as a ratio of integers
- Johann Lambert proved Pi is irrational in 1768
- The symbol for Pi (π) has been used regularly for 250 years
- Pi has been studied by the human race for 4,000 years
- Many mathematicians claim that it is more correct to say the a circle has an infinite number of corners than to view a circle as cornerless. Stop and think about that for a second.

- Pi was first calculated by Archimedes of Syracuse. He was reportedly so engrossed in his work that he did not notice when the Roman soldiers conquered the city of Syracuse. When a Roman soldier approached Archimedes, he yelled in Greek “Do not touch my circles!” The Roman soldier quickly cut off his head and moved on.
- If you printed a billion decimals of Pi in ordinary font it would stretch from New York City to Kansas. We recommend you don’t try and print out Pi!

**Find more information at (and our thanks to):**

http://www.exploratorium.edu/pi/history_of_pi/index.html

http://facts.randomhistory.com/2009/07/03_pi.html