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Pi is represented by the Greek letter π. Pi is never ending but it is usually represented as 3.14 - the same as March 14 (3/14)! The decimal places for pi continue past 3.14 and go on forever. Why do the numbers go on forever? Pi is not necessarily a number, but instead is something called a constant, or a constant number. That is because it can be used as a measurement for all circles, no matter how big or small. There are two measurements used with circles that helped mathematicians find pi. One is the diameter, which is the distance in the middle of the circle from edge to edge. The other is the circumference, or the distance around the circle. When you divide the circumference by the diameter, you get pi, whether the circle you’re measuring is the lid of a drink container or a circular field. All circles are a little more than 3 times longer around then they are wide, or 3.14. People still celebrate Pi Day to remember the discovery of those mathematicians…by having a delicious slice of pie!
Bytesized Facts
- The first person to calculate pi was Archimedes of Syracuse, an ancient Greek mathematician who lived from 287 - 212 BC. Before him, the ancient Babylonians and ancient Egyptians came close, but their numbers were slightly off, with the Babylonians coming up with pi = 3 and the Egyptians using a formula that made pi = 3.1605.
- Mathematicians didn’t start using the symbol π until the 1700’s, hundreds of years after Archimedes! The Welsh mathematician William Jones used the Greek word meaning circumference (periféreia or περιϕέρεια) and abbreviated it to its first letter - π.
- Pi Day is also Albert Einstein’s birthday! He was a physicist born on March 14, 1879.
