Celebrating Pi Day Mar 14, 2025

Celebrating Pi Day

Calculating the ratio of a circle"s circumference to its diameter is as easy as pi. Today is Pi Day, an event that celebrates this mathematical constant. This date was chosen because 3, 1, and 4 are the first three significant figures of pi (π) when it is written out. Pi is an irrational number, which means that it can"t be written as a fraction. When written out, its decimal representation goes on infinitely without repeating. The oldest attempts to calculate pi date back to ancient Babylon and Egypt, around 1900 BCE.

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Today in History

Mar 14, 2018Happy Pi Day!
Mar 14, 2019Rocky mountain pi
Mar 14, 2020A circular celebration
Mar 14, 2021Perfect timing
Mar 14, 2022Pi Day
Mar 14, 2023Pi Day
Mar 14, 2024Happy Pi Day!

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