March 14 marks Pi Day, an annual celebration of the mathematical sign pi. Founded in 1988 by physicist Larry Shaw, March 14 was selected because the numerical date (3.14) represents the first three digits of pi, and it also happens to be Albert Einstein’s birthday.

The first Pi Day celebration took place at the Exploratorium (Shaw’s place of work), a San Francisco-based interactive science museum, and featured a circular parade and the eating of fruit pies. It wasn’t until 2009, however, that it became an official national holiday when the U.S. House of Representatives passed legislation. (π) has been known for almost 4000 years—but even if we calculated the number of seconds in those 4000 years and calculated π to that number of places, we would still only be approximating its actual value.

Here’s a brief history of finding π.

History & Significance

The ancient Babylonians calculated the area of a circle by taking 3 times the square of its radius, which gave a value of pi = 3. One Babylonian tablet (ca. 1900–1680 BC) indicates a value of 3.125 for π, which is a closer approximation.

The Rhind Papyrus (ca.1650 BC) gives us insight into the mathematics of ancient Egypt. The Egyptians calculated the area of a circle by a formula that gave the approximate value of 3.1605 for π.

The Indian mathematician Aryabhat is most commonly credited with being the first to accurately calculate the estimated value of pi. Since it is an irrational, transcendental number, it continues to infinity—the pi-ssibilities are endless! The seemingly never-ending number needs to be abbreviated for problem-solving, and the first three digits (3.14) or the fraction 22/7, are commonly accepted as accurate estimations.

In mathematics, this infinite number 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. Pi is also essential to engineering, making modern construction possible.

Most everyone knows pi — the ratio of the circumference of a circle to its diameter. But how much do you really know about this magical number? Below are some fun facts about pi split up into tidy categories. Enjoy!

Fun Facts About Pi

Pi in society

• Pi Day is also Albert Einstein's birthday, along with the birthdays of Apollo 8 Commander Frank Borman, Astronomer Giovanni Schiaparelli, and last-man-on-the-moon Gene Cernan.
• There is a pi cologne.*

Computing pi

• Computing pi is a stress test for a computer -- a kind of "digital cardiogram.*
• The record for calculating pi, as of 2010, is 5 trillion digits (source: Gizmodo).

Random pi information

• If you were to print 1 billion decimal values of pi in the ordinary font it would stretch from New York City to Kansas.

Pi's numbers

• The first million decimal places of pi consist of 99,959 zeros, 99,758 ones, 100,026 twos, 100,229 threes, 100,230 fours, 100,359 fives, 99,548 sixes, 99,800 sevens, 99,985 eights, and 100,106 nines.*
• There are no occurrences of the sequence 123456 in the first million digits of pi -- but of the eight 12345s that do occur, three are followed by another 5. The sequence 012345 occurs twice and, in both cases, it is followed by another 5.*

Pi the number

• The fraction 22/7 is a well-used number for Pi. It is accurate to 0.04025%.^
• Another fraction used as an approximation to Pi is (355/113), which is accurate to 0.00000849%.^
• A more accurate fraction of Pi is (104348/33215). This is accurate to 0.00000001056%.^
• The square root of 9.869604401 is approximate Pi.^

The symbol pi

• In the Greek alphabet, pi (piwas) is the 16th letter. In the English alphabet, p is also the 16th letter.

Did you enjoy learning about these amazing facts about Pi? Start your experiential learning journey today and learn more about Pi and amazing mathematical concepts and facts. Check out the Practically app for more exciting content related to STEM subjects and learn experientially with lifelike 3D videos, simulations, and AR. Download the app for free today!

#piday #internationalpiday #practically #learnpractically #learningapp #3dvideos #AR #simulations