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# Jul22 Fun Holiday – Pi Approximation Day

July 22 is Pi Approximation Day. Also known as Casual Pi Day, the day is dedicated to the mathematical constant pi (π).

Pi denotes the relationship between a circle’s circumference and its diameter and is denoted by the fraction 22/7 which calculates approximately to 3.14. One of the most widely recognized mathematical constant, π, is an irrational number, the digits of which repeat in a random fashion and are never ending.

## Depends on Date Format

People in countries that write their dates in the date/ month format celebrate Pi Approximation or Casual Pi Day on 22 July or 22/7. On the other hand, those who write their date in month/ date format celebrate Pi Day on March 14 (3/14 or 3-14) because the first three digits of the date correspond to the first three digits of pi - 3.14.

## Move to Replace Pi

In recent years, some mathematicians and physicists have argued for the replacement of the π by tau and to celebrate Tau Day on June 28 instead of celebrating Pi Day or Pi Approximation Day.

## How to Celebrate?

Here are some ways you can celebrate this irrational, but fun holiday:

• Celebrate the day with lots of pie – remember a pie is also a circle so not only are you learning something about math, but also having fun while eating it!
• Have a pi contest. Whoever knows the most digits in the number takes home a pie.

## Did You Know...

...that the sequence 123456 does not occur in the first million digits of pi?

## Pi Approximation Day Observances

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