Pi is the ratio of a circle’s circumference to its diameter. Pi (*) has a decimal value of 3.14. In 1706, British mathematician William Jones devised the * symbol to represent the ratio, and it was later popularized by the Swiss mathematician Leonhard Euler.
Pi Approximation Day is celebrated on 22 July and Pi Day is celebrated on 14 March. Casual Pi Day is also known as Pi Approximation Day.
History of Pi Approximation Day
Nearly 4000 years have passed since Pi was first discovered. Circular dimensions were calculated using this value – approximated to 3.125 – by ancient Babylonians, around 250 B.C. Archimedes of Syracuse, one of the greatest ancient mathematicians, calculated pi for the first time. He found that pi fell somewhere between 3 1/7 and 3 10/71. Pi is occasionally referred to as the โArchimedesโ Constant.โ
Another brilliant mathematician, Zu Chongzhi, computed pi again in the mid-400s. Zu calculated Pi himself in a novel way since Archimedes’ books were lost. It was Zu and Archimedes who was the first to understand pi in any true sense.
Later on, mathematicians tried to approximate pi better using circumscribed and inscribed polygons. For 1,000 years, Archimedes used this method to calculate pi for the first time. In 1630, Austrian astronomer Christoph Grienberger reached 38 correct digits of pi using this method.
In the 16th- and 17th centuries, the infinite series (the sum of terms of an infinite sequence) revolutionized how pi is calculated. While Indian mathematicians discovered it between 1400 and 1500 A.D., it was European mathematicians like Leibniz and Gregory who popularized it a century later. The Greek symbol pi was first used to represent pi in 1706, despite pi being a well-known concept for centuries. William Jones, a Welsh mathematician, proposed this in 1737, but Leonhard Euler popularized it.
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Modern computing power is dedicated to approximating the infinite, irrational number to the fullest extent. The first time pi was calculated by a machine was in 1957, when George Reitwiesner and John von Neumann used an ENIAC computer. There were many intrepid mathematicians who followed. This method reached a million digits by 1973.
Significance of Pi Approximation Day
Pi Approximation Day serves as a reminder of the value of approximation in mathematics. In many cases, exact solutions are either impossible or unnecessary, and a close approximation is sufficient for practical purposes. This concept is beautifully embodied in the celebration of Pi Approximation Day, where 22/7 serves as a reminder of our quest for understanding through approximation.
So, while Pi Day on March 14 (3/14) celebrates the number itself, Pi Approximation Day is a playful twist that emphasizes the practicality of mathematics in everyday life. It’s a day for math enthusiasts to revel in the beauty of numbers and for the rest of us to appreciate the simplicity and utility of mathematical approximations. And, of course, it’s another excellent excuse to enjoy some delicious pie in the spirit of mathematical fun! Happy Pi Approximation Day!
Pi Approximation Day depends upon the format of the Date
According to timeanddate.com, the day depends on the format of the date. On 22 July or 22/7, some countries where dates are written in the date/month format celebrate Pi Approximation Day or Casual Pi Day. Meanwhile, those who write their dates in month/date format celebrate Pi Day on 14 March (3/14 or 3-14). Due to the fact that the first three digits of the date correspond to the first three digits of pi (3.14).
Facts about pi
- pi is irrational and is not equal to the ratio of any two whole numbers. Its digits do not repeat and for everyday calculations, an approximation like 3.14 or 22/7 is often used.
- The value of pi to 39 decimal places is 3.141592653589793238462643383279502884197.
- It’s indicated by the Rhind papyrus that ancient Egyptians used a value of 256/81 or about 3.16045.
How to Observe Pi Approximation Day
To observe this day, enthusiasts engage in various activities that are both fun and educational. One popular tradition is baking pies, as the word ‘pie’ sounds like ‘pi’, and a pie is a perfect circle, symbolizing the constant itself. Some people challenge themselves to memorize as many digits of ฯ as they can, turning it into a friendly competition with others. Educational institutions might organize events or lectures to delve deeper into the history and significance of ฯ in mathematics. Additionally, running in circles or organizing circular parades can be a humorous nod to the day. For those interested in the historical aspect, it’s fascinating to learn about the evolution of ฯ’s computation, from ancient civilizations to modern supercomputers. Pi Approximation Day serves as a reminder of the blend of education and enjoyment that mathematics can offer.
Observation Dates Pi Approximation Day
Pi Approximation Day, celebrated on July 22, is a whimsical holiday honoring the mathematical constant pi (ฯ).
| Year | Date | Day |
| 2019 | 22-Jul-19 | Monday |
| 2020 | 22-Jul-20 | Wednesday |
| 2021 | 22-Jul-21 | Thursday |
| 2022 | 22-Jul-22 | Friday |
| 2023 | 22-Jul-23 | Saturday |
| 2024 | 22-Jul-24 | Monday |
| 2025 | 22-Jul-25 | Tuesday |
| 2026 | 22-Jul-26 | Wednesday |
| 2027 | 22-Jul-27 | Thursday |
| 2028 | 22-Jul-28 | Saturday |
| 2029 | 22-Jul-29 | Sunday |
