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Utility used to calculate the content and circumference of a circle.
Calculating the circumference or area of a circle is not complicated, however, it is not absolutely accurate. This is due to Ludolph's number, which is transcedental, in layman's terms "you can't count the end".
Calculations of the Ludolph number began more than 6,000 years ago, and refinements continue to this day.

The Egyptians gave a value of Pi of 3.1605 while they too could have calculated Pi much more accurately. All they had to do was to roll the wheel in front of them and count all the turns. When, there would be 100 complete revolutions, measure the distance the wheel has travelled and divide that distance by the diameter of the wheel. The result would be 314 and some change.
If they made this measurement multiple times and took the mean of all the measurements, they could get a very accurate Pi value to a few decimal places.
Refinement of this value was therefore awaiting Archimedes.
He calculated it using polygons inscribed and circumscribed by a circle.
Dutch mathematician Ludolph van Ceulen (1540-1610) used this method to calculate Pi to 35 decimal places !!!! However, he devoted almost his entire life to it. Pi is also named after him as Ludolph's number.