3 ms·

> The duodecimal system, which is the use of 12 as a division factor for many ancient and medieval weights and measures, including hours, probably originates fr

• retrac 4y ago
  Yep. 60 seconds, 60 minutes, 12 hours. To the Sumerian mind that was apparently as nice and round as 100 seconds, 100 minutes, 20 hours. 60 is the smallest composite number with three prime factors, and divides evenly by 2, 3, 4, 5, 6, 10, 12, 15, 20, 30. Decimal only divides by 2 and 5. Makes arithmetic by hand a lot easier. Duodecimal has a similar advantage.
  • mandmandam 4y ago
    > 60 is the smallest composite number with three prime factors Er, that'd be 30 I think, but the main point stands.
    • BitwiseFool 4y ago
      2 is such a nifty prime, we multiplied by it twice. It was just too perfect not to.