Pi Day Tattoos | Red Arbor Tattoo Sioux Falls

March 14 is Pi Day. 3.14. So here's a post about pi.

Pi is the ratio of a circle's circumference to its diameter. Take any circle, measure around the outside and divide it by the width across the middle. You get the same number every time. 3.14159 and then more digits after that, forever. Pi is what mathematicians call an irrational number, which means it can't be written as a simple fraction. The decimal never ends and never falls into a repeating pattern.

Because of these things, it's called a "constant" number. A constant is a number that doesn't change. It doesn't matter how big or small the circle is. The ratio is always pi.

People have known about pi for a long time. Ancient Babylonians were working with it around 4,000 years ago. They estimated it at roughly 3.125. The Egyptians got close too. Archimedes, a Greek mathematician, was one of the first to calculate it with real precision around 250 BC by drawing polygons inside and outside of circles and measuring the edges. The more sides the polygon had, the closer the number got to pi.

The symbol comes from the Greek alphabet. It's the first letter of the Greek word "perimetros," which means perimeter. A Welsh mathematician named William Jones started using the symbol in 1706, and it stuck.

Today computers have calculated pi out to over 100 trillion digits. NASA uses 15 digits of pi to calculate spacecraft trajectories.

Cory Claussen, owner of Red Arbor Tattoo in Sioux Falls, has the pi symbol tattooed on his wrist. He says the design keeps him "well rounded."

If you want to talk about a pi tattoo or any other idea, reach out at redarbortattoo.com/contact.