Sexagesimal - Origin

Origin

It is possible for people to count on their fingers to 12 using one hand only, with the thumb pointing to each finger bone on the four fingers in turn. A traditional counting system still in use in many regions of Asia works in this way, and could help to explain the occurrence of numeral systems based on 12 and 60 besides those based on 10, 20 and 5. In this system, the one (usually right) hand counts repeatedly to 12, displaying the number of iterations on the other (usually left), until five dozens, i. e. the 60, are full.

According to Neugebauer, the origins of the sixty-count was through a count of three twenties. The precursor to the later six-ten alternation was through symbols for the sixths, (i.e. 1/6, 2/6, 3/6, 4/6, 5/6), coupled with decimal numbers, lead to the same three-score count, and also to the division-system that the Sumerians were famous for. In normal use, numbers were a haphazard collection of units, tens, sixties, and hundreds. A number like 192, would be expressed uniformly in the tables as 3A2 (with A as the symbol for the '10') but would in the surrounding text be given as XIxxxii i.e., hundred (big 10), sixty (big 1), three tens (little 10's), two (little 1's).