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Geek out with BART and celebrate a special Pi Day this year

pi symbol

Have you ever thought about pi on BART? Not the lemon meringue or deep-dish apple kind -- the mathematical one. Turns out pi is used in lots of ways at BART.

Pi is a mathemathical constant, the ratio of the circumference of a circle to its diameter. It's typically written as 3.14159 and is celebrated with Pi Day on March 14. 

This year is being called a "once in a lifetime" Pi Day. If you extend the digits out to the hour, minute and second, you get 3.14.15 (March 14, 2015) at 9:26:53 (just before 9:30 in the morning and evening). If you happen to be on a BART train at that time, give a cheer for pi! (You can download a PDF of all the pi examples, and some quizzes inside, to enlarge or print if you want to challenge the math lovers in your home). 

 

FIVE WAYS BART USES PI 

paint examplecable examplepipes examplewheel examplecurb example