Why is it used in 140? Hint, why is it not, what is not the
reason?
Babylonian 60 (no zero)
Mayan 20 (very early zero)
History of base ten: China, India (Cambodia zero, but maybe
much earlier in India)
Our system: Indian originations finalised in Islamic
mathematics, hence "Hindu Arabic"
Indigenous numeration - base 10 or 20 with words that reference
hands, feet, toes and fingers. Addition and multiplication
are common, division less so as it presumes homogenous
objects.
Common lunisolar calendar ideas.
Chumash (California) - base 4.
Yuki (California) - base 8 - count spaces between fingers
Bororo (Brasil) groups of 2 inside of base 20.
Hunters (based on Inuit and Ojibway
https://en.wikipedia.org/wiki/Ojibwe ) : numbers.
Sometimes number words are context dependent. Much of
numbers, and mathematics comes from controlling the environment or
specialisation - people relying on others to do tasks for
them. Read pp. 132-133. Shape categories “rounded” vs
“elongated” not angular, as it is mostly not natural.
Awareness of practical 1, 2, 3 dimensional distinctions.
Time. Distance as time.
I know nothing, but from here:
https://en.wikipedia.org/wiki/List_of_numeral_systems
3: some counting in Islam
4: Kharosthi - Ancient India
5: tally, aboriginal Australia
6: Indonesia
11: not a culture, but ISBN
12: Nigeria, Nepal, clocks, months, inches, dozen gross, great
gross
23 Papau New Guinea (place in the world famous for languages -
840!!)
27 PNG
32 Congo