Lesson plan

Undecimal

Undecimal (also known as unodecimal, undenary, and the base 11 numeral system) is a positional numeral system that uses eleven as its base. While no known society counts by elevens, two are purported to have done so: the Māori (one of the two Polynesian peoples of New Zealand) and the Pañgwa (a Bantu-speaking people of Tanzania). The idea of counting by elevens remains of interest for its relation to a traditional method of tally-counting practiced in Polynesia. During the French Revolution, undecimal was briefly considered as a possible basis for the reformed system of measurement. Today, undecimal numerals have applications in computer science, technology, and the International Standard Book Number system. They also occasionally feature in works of popular fiction. Any numerical system with a base greater than ten requires one or more new digits; "in an undenary system (base eleven) there should be a character for ten." To allow entry on typewriters, letters such as (as in hexadecimal), (the initial of "ten"), or (the Roman numeral 10) are used for the number 10 in base 11. It is also possible to use the digit ↊ ("dek"), the so-called Pitman numeral for 10 proposed in 1947 by Isaac Pitman as one of the two transdecimal symbols needed to represent base 12 (duodecimal).

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Article summary

Undecimal (also known as unodecimal, undenary, and the base 11 numeral system) is a positional numeral system that uses eleven as its base. While no known society counts by elevens, two are purported to have done so: the Māori (one of the two Polynesian peoples of New Zealand) and the Pañgwa (a Bantu-speaking people of Tanzania). The idea of counting by elevens remains of interest for its relation to a traditional method of tally-counting practiced in Polynesia. During the French Revolution, undecimal was briefly considered as a possible basis for the reformed system of measurement. Today, undecimal numerals have applications in computer science, technology, and the International Standard Book Number system. They also occasionally feature in works of popular fiction. Any numerical system with a base greater than ten requires one or more new digits; "in an undenary system (base eleven) there should be a character for ten." To allow entry on typewriters, letters such as (as in hexadecimal), (the initial of "ten"), or (the Roman numeral 10) are used for the number 10 in base 11. It is also possible to use the digit ↊ ("dek"), the so-called Pitman numeral for 10 proposed in 1947 by Isaac Pitman as one of the two transdecimal symbols needed to represent base 12 (duodecimal).

Key claims

  1. publication date: 1820 — source: Wikipedia · confidence 0.95
  2. publication date: 1826 — source: Wikipedia · confidence 0.95
  3. publication date: 1839 — source: Wikipedia · confidence 0.95

Discussion questions

  1. Summarise the article in your own words. Which single claim would you verify first, and why?
  2. The record states that the publication date is "1820". What evidence would count against this claim?
  3. The record states that the publication date is "1826". What evidence would count against this claim?
  4. The record states that the publication date is "1839". What evidence would count against this claim?
  5. Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
  6. If two sources disagreed about one of these facts, what would you need in order to trust one over the other?

Bibliography

  1. Wikipedia https://en.wikipedia.org/w/index.php?oldid=1375440958

Key claims and bibliography are generated from the same tracked claims and sources as the article page.