Definitions

# Quinary

[kwahy-nuh-ree]
Quinary (base-5) is a numeral system with five as the base. This originates from the five fingers on either hand.

In the quinary place system, five numerals from 0 to 4, are used to represent any real number. According to this method, five is written as 10, twenty-five is written as 100 and sixty is written as 220.

## Usage

Many languages use quinary number systems, including Gumatj, Nunggubuyu,, Kuurn Kopan Noot and Saraveca. Of these, Gumatj is the only true "5-25" language known, in which 25 is the higher group of 5. The Gumatj numerals are shown below:
Number Numeral
1 wanggany
2 marrma
3 lurrkun
4 dambumiriw
5 wanggany rulu
10 marrma rulu
15 lurrkun rulu
20 dambumiriw rulu
25 dambumirri rulu
50 marrma dambumirri rulu
75 lurrkun dambumirri rulu
100 dambumiriw dambumirri rulu
125 dambumirri dambumirri rulu
625 dambumirri dambumirri dambumirri rulu

A decimal system with 5 as a sub-base is called biquinary, and is found in Wolof and Khmer. A vigesimal system with 5 as a sub-base is found in Nahuatl and the Maya numerals.

Roman numerals are a biquinary system. The numbers 1, 5, 10, and 50 are written as I, V, X, and L respectively. Eight is VIII and seventy is LXX.

The Chinese and Japanese versions of the abacus use a biquinary system to simulate a decimal system for ease of calculation.

Urnfield culture numerals and some tally mark systems are also biquinary.