# It's Time for Pi!

Updated: Mar 16, 2021

March 14 marks the annual celebration of Pi day, as the month and day number corresponds with the first three digits of Pi, 3.14. I guess we should also wish Albert Einstein a very happy birthday and maybe bake a Pi in his honour. The genius we have to thank for this celebration and loophole that allows us to indulge in pies all day is physicist Larry Shaw. Pi day was firstly celebrated in 1988 and it featured parades, pie eating competitions and interactive games hosted by the Exploratorium, a museum based in San Francisco. By 2009 Pi day became a official national holiday. But why is Pi so important and why do we have a whole day reserved for it?

Pi is a irrational, transcendental number meaning it goes on to infinity. The mathematician Archimedes was credited for being the first to accurately calculate the estimated value of Pi. The word Pi is derived from the Greek word “Perimetros” which directly translates to: perimeter, circumference . The fact that Pi is crucial because of what it represents in relation to a circle—it’s the constant ratio of a circle’s circumference to its diameter.

The Babylonians calculated the area of a circle by taking 3 times the square of the radius which gave Pi to be 3.125 according to a Babylonian tablet that was dated cc 1680. Then again the Rhind Papyrus (1605) that belonged to the mate mathematicians of ancient Egypt gives another formula for Pi that results in Pi being 3.1605.

So how did we get to 3.14? Archimedes of Syracuse during 287-212, approximated the area of the circle by using the Pythagorean Theorem to find the areas of two regular polygons: the polygon inscribed within the circle and the polygon within which the circle was circumscribed. Since the actual area of the circle lies between the areas of the inscribed and circumscribed polygons, the areas of the polygons gave upper and lower bounds for the area of the circle. Archimedes knew that he had not found the value of π but only an approximation within those limits. However, he demonstrated that π is between 3 1/7 and 3 10/71.

The Greek letter π was introduced by William Jones in 1706 and was later popularized by

Leonhard Euler who adopted it in 1737.

Nowadays, Pi has been calculated to over 1 trillion decimal places and the calculations are still ongoing. The aim of this big celebration is to increase children’s interest in mathematics and sciences. Teachers, scientists and mathematicians around the world celebrated with sweet pies, interactive games and fun math problems. How did you celebrate? Let us know on The Nest Instagram page or our The Nest website.