Pi Day: Great for math and tastebuds

In 1706, the British astronomer John Machin calculated π to 100 digits (by hand of course). His trick was to notice that π = 16A – 4B where A and B are given by. This is an excellent discovery, because the series for A involves 

The Greeks never figured this out, but perhaps you can. How can you determine the value of pi using two steel balls?

The Greeks never figured this out, but perhaps you can. How can you determine the value of pi using two steel balls?

Pi Day (3/14) is the unofficial holiday dedicated to pi. Pi is the ratio of a circle's circumference to its diameter, and it's an irrational number, so it can't be expressed as a simple fraction of two integers. The number starts out with 

Why pi? The mathematical constant that every schoolchild has at least heard of—I hope—seems to pop up in so many seemingly unrelated areas. Its mystique may be one of the engaging hooks that make a child a scientist. When pi is around, something