In the Christian Bible, 2 Chronicles 4:2 describes the construction of the “sea” of Solomon’s temple. This was a circular cast-metal laver or basin used for ritual cleansing. Its diameter is described as ten cubits from one brim to the other, and its circumference was measured by a line of thirty cubits.
Critics have sometimes scoffed at this verse, claiming that it clearly uses an erroneous value for pi. Of course, the obvious response is that the quoted figure for the diameter was not meant to be an exact measurement, but simply rounded to nearest whole number (or perhaps it didn’t even have to be rounded that much if the circumference was an inside measurement, not including the width of the brim). Still, if the inaccuracy of these things bothers you, cheer up! You no longer need resort to such embarrassing explanations. After hours of hard work I have come up with a genuine mathematical proof that the measurements given in the Bible are literally true!
- We start by defining a value x to simplify the math:
- Let x = 5π + 15
- Next, we write the formula for the circumference of a circle, plugging in the diameter of 10:
C = 10π
- Add 30 to each side and substitute our handy value x:
- C + 30 = 10π + 30
- C + 30 = 2 (5π + 15)
- C + 30 = 2x
- Multiply each side by (C − 30):
- (C + 30) (C − 30) = 2x (C − 30)
- C2 − 900 = 2Cx − 60x
- Add x2 to each side and rearrange the terms:
- C2 − 900 + x2 = 2Cx − 60x + x2
- C2 − 2Cx + x2 = 900 − 60x + x2
- Factor and simplify:
- (C − x)2 = (30 − x)2
- (C − x) = (30 − x)
- C = 30
- QED!
PS: Just kidding!
But speaking of pi, here’s a formula I came up with a few years ago to make it easier to remember:
π = (12.3 + 4 + 5) / 6.78Don’t believe this works? Try it!
This page copyright © 2007-2015 Edward A. Morris. Created July 27, 2007. Last updated December 2, 2015.