Tag Archives: Pi

Happy Summer Pi Day!

Math teachers love March 14, the day where we have a built-in excuse to strong-arm students into bringing cookies, cakes, and pies to class, all under the clever guise of celebrating our irrational friend.  But while we celebrate and embrace 3.14, its fractional buddy 22/7 often trudges on without fanfare.  So, on this July 22, consider this challenge:

  • Which approximation of pi,  3.14 or 22/7, is better?

What spirited debates which can take place by assigning students a side to defend?  A quick visual inspection of the protagonists, labeled on a number line, provides some initial evidence:

Number Line 1

Additionally, this is a great time to discuss and compute error.  Just how far away are we from what we would like to estimate?  And how good of a job have we done?

Number Line 2

Evelyn Lamb provides some pi anecdotes in this month’s Scientific American.  How many digits of Pi does NASA utilize in calculations?  Why do people seek to memorize the digits of pi?

So raise a glass to the “real” pi day!  Off to seek some fresh blueberry pie……