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When is National Pi Day in 2021?

National Pi Day in 2021 is on the Saturday, 3rd of Apr (4/03/2021).

National Pi Day is on the 93th day of 2021. There are 272 days left in the year.

National Pi Day Facts

  • Date: Apr 03, 2021
  • Fun
  • Also Called: Pi Day
  • Celebrations: Eating, Partying, Contests
National Pi Day iImage Credit: PixaBay.com

Pi (π) is a mathematical symbol representing the ratio of the circumference of a circle to its diameter. The ratio is approximated as 3.14, but it’s calculated to over one trillion digits beyond the decimal point. Pi (π) is a vital key in Mathematical geometry and equations. The surface area and perimeter of circular objects depend on the symbol for accurate results. Observed on March 14th, National Pi Day is an opportunity for Math enthusiasts to showcase their love for numbers. National Pi Day should however not be confused with Pi Approximation Day observed ion June 22nd or Two Pi Day marked on June 28th.

Who Invented Pi?

According to historians, the first person to calculate pi was Archimedes of Syracuse. He was one of the ancient Greek mathematicians of the world, and he lived in the 3rd century. Archimedes used the Pythagorean Theorem alongside two regular polygons to calculate the area of a circle. Archimedes approach was theoretical, and it showed that pi was between 3 1/7 and 3 1/10. The use of Pi was popularized in the 1700s by William Jones and Leonhard Euler.

History of National Pi Day

Pi (π) has a rich history. Various ancient civilizations have been linked to the calculation of the Pi (π). Among them are Egyptians and Babylonians. Babylonians determined the area of a circle by squaring the radius and then multiplying it by three. This gave a value of 3 which is a close approximation to pi. For the Egyptians, they would calculate the area of a circle by a formula that approximated pi as 3.1605.

Pi is also biblical. In the Old Testament, (1 Kings 7:23), a circular pool is said to be 30 cubits around and ten cubits wide. This again gives the value of pi as 3 or thereof.

The first records of National Pi Day are traced in 1988 in San Francisco. The day was meant to draw attention to the STEM fields (science, technology, engineering, and math.) The celebrations were organized by physicist Larry Shaw, who led the public in marching around circular spaces and consuming fruit pies.

On March 12, 2009, a non-binding resolution was passed by the US Congress where March 14th was officially recognized as the National Pi Day. The entire month of March is also observed as the National Pi month. The date was chosen since it coincides with the first three significant digits of pi which are 3, 1 and 4. Interestingly, Albert Einstein’s birthday also falls on March 14th.

How to Celebrate National Pi Day

You can observe National Pi Day by eating pies and other circular treats. Pi and pie are English homophones, and the coincidental circular form of pie makes it the best treat of the day.

If you love Mathematics, mark the day by holding a pi memorization contest with friends. Although pi can be calculated to infinite numbers, figure out who among your friends can recite most of the numbers as they follow each other. Google has a training app for the same to help you in the contest.

Another great way to mark this day is by celebrating Albert Einstein’s birthday. You can attend celebrations in Princeton, New Jersey where a major event to mark the pi day and Einstein’s birthday is held. Some of the Pi Day activities you can take part in during the event include dressing like the Nobel Prize winner. If declared the winner of the Einstein’s Look-Alike contest then you will be lucky to go home with a great award. The German-born theoretical physicist lived in Princeton for 20 years while working at one of the institutes there.

You can also dazzle your friends by posting a pi-themed trivia on social media. Remember to share with them the practical problems in real life that pi help us solve. Spread all this enthusiasm using the hashtag #NationalPiDay.

Interesting National Pi Day Fun Facts

- Pi (π) is the 16th digit of the Greek alphabet.

- In the 18th century, Pi (π) was proved to be an irrational number. This means that it is decimal representation is infinite and never repeats.

- Lu Chao from China holds the World Record for memorizing the first 67,890 digits of the Pi (π).

- Only the first 39 digits of Pi (π) are required to give an accurate answer of any Pi (π) mathematical problems.

National Pi Day Observances

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List of National and Regional Public Holidays of United States in 2022

SaturdaySatJan 01, 2022Jan 01New Year's Day
MondayMonJan 17, 2022Jan 17M L King Day
MondayMonFeb 21, 2022Feb 21Presidents' Day
FridayFriApr 15, 2022Apr 15Good Friday
SundaySunApr 17, 2022Apr 17Easter Sunday
MondayMonMay 30, 2022May 30Memorial Day
SundaySunJun 19, 2022Jun 19Juneteenth
MondayMonJul 04, 2022Jul 04Independence Day
MondayMonSep 05, 2022Sep 05Labor Day
WednesdayWedOct 19, 2022Oct 19Columbus Day
FridayFriNov 11, 2022Nov 11Veterans Day
ThursdayThuNov 24, 2022Nov 24Thanksgiving Day
SundaySunDec 25, 2022Dec 25Christmas

List of Popular Celebration Days of United States in 2022

WednesdayWedJan 12, 2022Jan 12National Pharmacists Day
WednesdayWedJan 19, 2022Jan 19National Popcorn Day
WednesdayWedFeb 02, 2022Feb 02National Signing Day
WednesdayWedFeb 02, 2022Feb 02Groundhog Day
FridayFriFeb 04, 2022Feb 04National Wear Red Day
WednesdayWedFeb 09, 2022Feb 09National Pizza Day
SundaySunFeb 13, 2022Feb 13Galentine's Day
MondayMonFeb 14, 2022Feb 14Valentine's Day
TuesdayTueFeb 15, 2022Feb 15National Bagel Day
FridayFriFeb 18, 2022Feb 18National Drink Wine Day
TuesdayTueFeb 22, 2022Feb 22National Margarita Day
TuesdayTueMar 01, 2022Mar 01National Pancake Day
FridayFriMar 04, 2022Mar 04National Employee Appreciation Day
SundaySunMar 06, 2022Mar 06National Walking Day
MondayMonMar 07, 2022Mar 07National Cereal Day
MondayMonMar 14, 2022Mar 14National Napping Day
MondayMonMar 14, 2022Mar 14National Pi Day
MondayMonMar 14, 2022Mar 14National Walkout Day
SundaySunMar 20, 2022Mar 20National Proposal Day
WednesdayWedMar 23, 2022Mar 23National Puppy Day
WednesdayWedMar 30, 2022Mar 30National Doctor Day
ThursdayThuApr 07, 2022Apr 07National Burrito Day
ThursdayThuApr 07, 2022Apr 07National Beer Day
MondayMonApr 11, 2022Apr 11National Pet Day
TuesdayTueApr 12, 2022Apr 12National Grilled Cheese Day
ThursdayThuMay 05, 2022May 05National Day Of Prayer
SundaySunMay 08, 2022May 08Mother's Day
WednesdayWedMay 25, 2022May 25National Wine Day
WednesdayWedMay 25, 2022May 25National Towel Day
FridayFriJun 03, 2022Jun 03National Donut Day
WednesdayWedJun 08, 2022Jun 08National Best Friends Day
SundaySunJun 19, 2022Jun 19Father's Day
TuesdayTueJun 21, 2022Jun 21National Selfie Day
WednesdayWedJun 22, 2022Jun 22National Kissing Day
TuesdayTueJul 12, 2022Jul 12Amazon Prime Day
WednesdayWedJul 13, 2022Jul 13National French Fry Day
ThursdayThuJul 14, 2022Jul 14National Nude Day
SundaySunJul 17, 2022Jul 17National Ice Cream Day
WednesdayWedJul 20, 2022Jul 20National Hot Dog Day
SundaySunJul 24, 2022Jul 24National Tequila Day
FridayFriJul 29, 2022Jul 29National Chicken Wings Day
MondayMonAug 01, 2022Aug 01National Girlfriend Day
SundaySunAug 07, 2022Aug 07National Sister Day
SundaySunSep 18, 2022Sep 18National Cheeseburger Day
MondayMonOct 03, 2022Oct 03National Boyfriends Day
TuesdayTueOct 04, 2022Oct 04National Taco Day
TuesdayTueOct 04, 2022Oct 04National Vodka Day
SundaySunOct 09, 2022Oct 09Leif Erikson Day
SaturdaySatOct 15, 2022Oct 15Sweetest Day
SaturdaySatOct 29, 2022Oct 29National Cat Day
MondayMonOct 31, 2022Oct 31Halloween
ThursdayThuNov 03, 2022Nov 03National Sandwich Day
SundaySunNov 06, 2022Nov 06Daylight savings
FridayFriNov 25, 2022Nov 25Black Friday
MondayMonNov 28, 2022Nov 28Cyber Monday
SaturdaySatDec 03, 2022Dec 03Candle Day
FridayFriDec 09, 2022Dec 09National Pastry Day
FridayFriDec 16, 2022Dec 16National Ugly Sweater day