What is Pi?
According to The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide, pi is the “Ratio of the circumference of a circle to its diameter. Pi is an irrational number: it cannot be expressed as the ratio of two integers, and its expression as a decimal never terminates and never starts recurring. The value of pi is 3.1415926, correct to seven decimal places. Common approximations to pi are 22/7 and 3.14, although the value 3 can be used as a rough estimation.
For example, a piece of string tied around the circumference of a mug will measure approximately three times the diameter of the mug.”
Why Pi Day?
The Wikipedia article on Pi Day explains that “Pi Day is observed on March 14 (3/14 in the month/day format) since 3, 1, and 4 are the first three significant digits of π. … In 2009, the United States House of Representatives supported the designation of Pi Day. UNESCO’s 40th General Conference decided Pi Day as the International Day of Mathematics in November 2019.”
The Exploratorium in San Francisco started Pi Day. Take a look at their article on “A Brief History of Pi.”
Coincidentally, Pi Day is also Albert Einstein‘s birthday. (Topic page on Einstein via the library’s Credo Reference database)
Pi Day in the Learning Commons
Library sources on Pi
A history of the circle: mathematical reasoning and the physical universe (print book, 1999) by Ernest Zebrowsk
“An investigation of how past attempts by scientists to discover the perfect circle led to major discoveries of the physical universe. Throughout, the author emphasizes the concepts underlying the mathematical calculations presented, and how they link to real-life examples.”
Visions of infinity: the great mathematical problems (print book, 2013) by Ian Stewart
“An approachable and illuminating history of mathematics as told through fourteen of its greatest problems.”
Irrational numbers: Pi and pies (5-min. video, 2014, via Films on Demand) by ClickView Pty Limited
“The clip explains how the irrational number pi (p) is derived and provides an example of its practical application in calculating the area of different-sized pie tins.”
Calculate Pi with Will Webber
Whatcom’s very own math instructor, Will Webber, invites all to come help calculate Pi:
“This Thursday is Pi day (3/14). In celebration, I am organizing as many people as possible to calculate pi without using any computing devises. We will use paper, pencil and brain power.
The festivities will begin at 10:00 AM on the third floor of the Learning Commons (in the space in front of the math center). We will conclude the calculation at 3:14:15 PM and see how we did. I’m hoping for 25 to 30 decimal places.
The calculation is broken into many smaller calculations. I can use people for as much or as little time as each person has. There is no high-level math here. If you can add, subtract, multiply or divide, I can use you. If you know of anyone who can add, subtract, multiply, or divide, I can use them. The more people the better. Please let your students know.
Even if you don’t want to join in on the fun of number crunching, please feel free to stop by and just celebrate this most amazing number.”