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WORD OF THE DAY

pi

In math, pi is the ratio of a circle's circumference to its diameter. No matter how large or small a circle is, this ratio will always equal pi, or approximately 3.14.

Although it sounds just like pie, this kind of pi isn't a delicious dessert with a pastry crust. Instead, it's an irrational number, one that can't be written as a simple fraction but instead goes on infinitely after the decimal point. Rounded to 3.14, it's close enough to help you calculate the diameter, radius, or area of a circle in your geometry class. Pi is an abbreviation of the Greek periphereia, "periphery."


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