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Pi Day: An Infinite Number of Ways to Celebrate

Pi Video Promo

On Friday, math enthusiasts celebrate pi, the infinite number representing the relationship between a circle's circumference and its diameter. Represented by the Greek letter pi, the number is usually shortened to 3.14, so festivities take place on March 14 or 3/14.

Across the country, math aficionados trade pi recipes, hold pizza parties, and recite as many digits of the never-ending number as they can remember. (Listen to a recitation by Mark Umile, North American record-holder for memorizing pi.)

Physicist Ron Hipschman talks with host Ira Flatow about the all-day pi celebration taking place at the Exploratorium in San Francisco.

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