1. Definition of percentage:
In mathematics, a percentage is a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign, "%", or the abbreviation "pct." A percentage is a dimensionless number (pure number).
2. History of percentage:
The concept of percent was originally brought about by ancient Romans in the use of levying tax on goods.
The term "per cent" is derived from the Latin per centum, meaning "by the hundred". The sign for "per cent" evolved by gradual contraction of the Italian term per cento, meaning "for a hundred". The "per" was often abbreviated as "p." and eventually disappeared entirely. The "cento" was contracted to two circles separated by a horizontal line, from which the modern "%" symbol is derived.
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