Did You Know

What are Roman Numerals?

Roman numerals are a numeric system which is represented by a combination of Latin alphabet letters.

What are Roman Numerals?

Roman numerals is a system of numbers, which are represented by the combination of Latin alphabet letters. The numeric system was the standard way of writing numbers in Europe during the late Middle Ages. Roman numerals were useful even after the fall of the Roman Empire, but from the fourteenth century, the Hindu-Arabic replaced them since it was a convenient system. The process of replacement was slow, making the use of Roman numerals to have persistent use in minor applications in the modern day. The following are the symbols that provide the foundation of Roman numerals in the contemporary methods:

Roman numeral system symbol

Decimal system value















Standard Forms

The standard forms of Roman numerals are the current usage of the Roman numbers with universal convention. Numbers in Roman numerals contain the combination of symbols and adding the values. For example, I is the Roman number for one and II is the Roman number for two. The formation of II involves combining of two Roman letters for one. Similarly, III comprises of three ones, but VIII is formed through a combination of V (five) and III (three) which means an addition of the value of the symbols. Therefore, the arrangement of Roman numerals is based in the order of values of the symbols such that the final combination represents the actual value in the decimal system. It is important to note that the system does not require "place keeping" since each numeral represents a fixed value and not the multiples of one, ten and more by position. The Roman numeral IV (four) is five (V) minus I (one) while VI (six) is five (V) plus one (I).

Alternative Forms

Apart from the above standard forms, alternative forms of Roman numerals had their usage in ancient Rome with inconsistence in feudal and present times. Typically, additive forms of the Roman symbols are common in inscriptions dating such that the numbers four and nine, for example, are IIII and VIIII respectively rather than IV and IX as in the standard forms. Moreover, the number eighteen is alternatively written as IIXX or XIIX instead of XVIII since, in Latin, the number is regarded as a number that is 22 less two.

In other alternative forms, V and L have no use in the system. Therefore, VI and LX would have cases of IIIIII and XXXXXX respectively. In the faces of clocks using Roman numerals, IIII rather than IV usually shows the four o’clock point, but the nine o'clock position uses the standard form. The clocks using this format were mostly the early ones since in the current clocks such as the one Big Ben in London uses the standard way for the four o'clock point. Lastly, there were varying Roman numeral representations of 900 during the start of the twentieth century. The number is typically CM according to the standard forms, but in several inscribed dates such as Saint Louise Art Museum, the inscription of 1903 is MDCDIII instead of MCMIII.

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