March 14 is known as Pi Day because the mathematical representation of pi is 3.14. Actually, it is 3.14159265259 and carries on infinitely. Pi is the ratio of the circumference of a circle to its diameter. No matter the size of any circle, when you divide its circumference by its diameter you will always get pi. For this mathematical phenomenon, March 14 is celebrated by math lovers everywhere.
Pi Equals Pie TShirts

Clever Tshirts shouldn't be afraid of a pun. A Tshirt of a jackolantern with the symbol for pi carved in it would stand for pumpkin pi. A shirt with a sliced open apple with the pi symbol for pi would represent apple pie. To go the other direction, with the pun being mathematical, go with a picture of a pie, with the pi symbol as part of the crust markings. Add the text: "Too much pi is increasing my circumference." You can also replace the text of words that start with the symbol for pi. For example, "Pirate" or "Pilot," and add a graphic representing either profession. You might begin your Pi Day celebration by going to "pilates" class and end it with a glass of pinot noir.
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