## Tuesday, March 14, 2017

### Paradise ponders, puppy birthdays and irrational numbers...

Paradise ponders, puppy birthdays and irrational numbers...  Today (3/14/2017) is the first birthday of Mako and Cabo, our little field spaniel puppies.  The video at right is one I took of them last June, when they were about 3 months old.  It captured one of their play “battles” in slow motion.  They still do the same thing today, though the physics are now a bit different since they weight a lot more.

We celebrated this morning by giving them some half-and-half with their morning kibble, and by letting them have two bananas instead of their usual one (split between four dogs).  The little puppies have no idea why they got this bonanza this morning, but (trust me on this) they weren't complaining. :)

Today is also Pi Day, commemorating that most famous of irrational numbers: pi.  Of course there's a web site dedicated to it, where you can find the first million digits of pi if you're looking for some reading material.

A few years ago I read a study that attempted to measure adult innumeracy in various countries around the world.  There were two questions related to pi on there.  The first one asked for a definition of pi.  The second asked the test taker to write down as many digits of pi as he or she knew.  Americans stood out for their ignorance of these.  I don't remember the exact numbers any more, but it was something like 15% of Americans could define pi as the ratio of the circumference of a circle to its diameter.  The average number of digits known by Americans was less than one.  That means a great many Americans didn't even know that the first digit was “3”!  I remember comparing those results with those from Estonia, and being appalled at the gap.  The majority of Estonians could define pi, and the average number of digits was over 4.  On a good day, after my morning tea, I can remember 6 or 7 digits – which makes me extraordinary for an American, and slightly above average for an Estonian.

A friend of mine, Clay M., came up with a clever and fun way to help his daughters understand pi.  They baked a pizza, then cut it up into a lot of skinny slices, 20 or so.  Then they arranged these slices side-by-side, alternating the pointy end up or down.  This made a rough rectangle whose height was the radius of the pizza (diameter/2) and whose length was pi * radius.  By simply measuring the length of the “rectangle” they could measure pi – and then they got to eat the pizza.  Win!