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# Duodecimal

The base-12 number system composed of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B. Such a system has been advocated by no less than Herbert Spencer, John Quincy Adams, and George Bernard Shaw (Gardner 1984). In fact, duodecimal still has its advocates, some of whom term it "dozenal."

Some aspects of a base-12 system are preserved in the terms dozen and gross applied to the quantities 12 and 144, respectively.

The following table gives the duodecimal equivalents of the first few decimal numbers.

 1 1 11 B 21 19 2 2 12 10 22 1A 3 3 13 11 23 1B 4 4 14 12 24 20 5 5 15 13 25 21 6 6 16 14 26 22 7 7 17 15 27 23 8 8 18 16 28 24 9 9 19 17 29 25 10 A 20 18 30 26

12, Base, Decimal, Dozen, Gross, Hexadecimal

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## References

Andrews, F. E. "An Excursion in Numbers." Atlantic Monthly 154, 459-466, Oct. 1934.Andrews, F. E. "My Love Affair with Dozens." Mich. Quart. Rev. 11, 104-110, Spring 1972.Dozenal Society of America. http://www.dozenal.org/.Gardner, M. The Sixth Book of Mathematical Games from Scientific American. Chicago, IL: University of Chicago Press, pp. 104-105, 1984.

Duodecimal

## Cite this as:

Weisstein, Eric W. "Duodecimal." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Duodecimal.html