> Telugu (a language of southern India) has an interesting traditional numeric system: base ten for integers, and base four for fractions.
If they do consistently that is not too bad. Compare that with imperial units, which, depending on the quantity and sometimes its magnitude, uses
- base 10 for integers and base 12 for fractions (lengths in feet and inches). Alternatively, base 10 for mikes, base 5,280 for feet’s in a mile, base 12 for inches in a foot.
- base 10 for integers and base 14 for fractions (weights in stone and pound). Alternatively, there’s a base 112 when measuring in long tons and stones or 1,016 when using long tons and pounds)
- base 10 for integers and base 4 for fractions (lengths in miles and quarter/half miles)
And that’s ignoring specific units for weighing gold, diamonds, etc.
You left out perhaps the most widespread and important example! Many western European cultures, going back I think to Charlemagne, had a monetary system in which a pound was divided into 20 shillings / solidi, and each shilling was divided into 12 pence / denarii. This system persisted in England into the 1970s but it was widespread before the 20th century. For example, in France each livre was divided into 20 sou, and each sou into 12 denier, until 1795.
Leonardo of Pisa's famous book "Liber Abaci" spends a lot of time showing how to do arithmetic on these complicated mixed units, and has an interesting notation for them. If you're interested see https://blog.plover.com/math/liber-abaci-fractions.html .