π is one of the most widely-known mathematical constants both inside and outside the mathematics/scientific community and it has been around for a very long time!
The ratio of the circumference to the diameter of a circle is constant (namely, pi) and has been recognized for as long as we have written records.
A ratio of 3:1 appears in the following biblical verse:
“And he made a molten sea, ten cubits from the one brim to the other: it was round all about, and his height was five cubits: and a line of thirty cubits did compass it about.” (I Kings 7, 23; II Chronicles 4, 2.)
The ancient Babylonians generally calculated the area of a circle by taking 3 times the square of its radius (=3), but one Old Babylonian tablet (from ca. 1900-1680 BC) indicates a value of 3.125 for pi.
π is commonly defined as the
ratio of a
circle‘s
circumference C to its
diameter d.
The ratio
C/
d is constant, regardless of the circle’s size. For example, if a circle has twice the diameter of another circle it will also have twice the circumference, preserving the ratio
C/
d.
Of course, there is humor in math, so here’s the joke of the day:
What is the official animal of Pi Day? Why, the pi-thon, of course!
Mathematically yours on the “mathy” day,
Carollee
