happy pi day

(I have previously posted about some of these links, however, now that I am actually a "real" math teacher, I think it is important to do a proper pi day post.)

Today, March 14, or 3.14, many schools and other mathematically-inclined people are celebrating pi day.

Pi is a mathematical value whose dates history back to 1900 BC!

Pi, Greek letter (), is the symbol for the ratio of the circumference of a circle to its diameter. It is approximately 22/7 and is usually calculated to 3 digits, 3.14. With the use of computers, Pi has been caculated to over 51 billion decimal places. Pi is an irrational number meaning it will continue infinitely without repeating. - piday.org

In honor of the event, you might want to learn the pi song. If singing it is not enough, you can watch the video (a rather bizarre parody of Zoom).

Or, learn "How to Memorize Pi." Even better, use the on-line Pi Trainer. (The current world record is 100,000 decimal places, set on October 3, 2006 by Akira Haraguchi - it took him 16 hours to recite!)

Or just gaze at the first million digits.... Also, everyone's birthday is allegedly somewhere in pi's repeating digits... want to find yours?

One researcher even lets you set pi to music?! Even writers cannot resist the temptation of this irrational number. Read Cadaeic Cadenza and learn how this story is pi-related.

Finally, you could check out this pi merchandise.

Imagine the party on March 14, 2015!

ADDED: Read about the Eminem parody "Lose Yourself" recorded by "Pi Diddy", a 7th grade math teacher for students in Louisville, KY. As you might imagine, someone made a video. Pretty clever....

the five-second rule

In the Ohio State - Wisconsin game on February 25, the most memorable moment of the game wasn't a three-pointer or the final score. Coach Tad Matta's actions were the big news when he picked up his recently-ejected gum from the floor and popped it back into his mouth.

According to a Chicago Tribune article, Matta said,

I have two daughters and they taught me a three-second rule. I have three seconds to pick it up off the floor and it’s still OK. I picked it up quick...

Not surprisingly, the incident found its way to YouTube.

With all this media attention, you might want to consider just how scientifically accurate is five- (or three-) second rule really is.

Jillian Clarke of Chicago High School for Agricultural Sciences tested the theory in 2003. She performed tests by dropping Gummi Bears and fudge-striped cookies onto ceramic tiles. Some of those tiles had been treated with E. Coli (a bacteria present in our intestines, but when ingested in large quantities, can give us symptoms of food poisoning). She discovered the following: (as quoted in the Tribune)

• Seventy percent of women and 56 percent of men are familiar with the five-second rule, and most use it to make decisions about tasty treats that slip through their fingers.
• Women are more likely than men to eat food that has been on the floor.
• Cookies and candy are much more likely to be picked up and eaten than cauliflower or broccoli.
• And, if you drop your food on a floor that does contain micro-organisms, the food can be contaminated in 5 seconds or less.

A University of Arizona researcher Charles Gerba points out that surfaces can be misleading. The average office desk, for example, harbors 400 times more bacteria than the average toilet seat. And teachers’ work spaces have more bacteria than most other professions. (Great.)

A Snopes.com article explains simply, "Unlike baseball, when food hits the floor, it's out."