Roman Numerals

Roman Numerals, or Roman Notation, is supposed to have been used by the Romans; hence its name. The system of Roman notation is not well adapted to the purposes of numerical calculation; it is principally confined to the numbering of chapters and sections of books, public documents, etc. The system employs seven capital letters to express numbers. Thus, I=1, V=5, X=10, L=50, C=100, D=500, M=1000. The Roman system of notation is founded on five principles.

1. Repeating a letter repeats its value. Thus II=2, XX=20, CCC=300.

2. If a letter of any value is placed after one of greater value, its value is added to that of the greater, Thus, XI=11, LX=60, DC=600.

3. If a letter of any value is placed before one of greater value, its value is subtracted from that of the greater. Thus, IX=9, XL=40, CD=400.

4. If a letter of any value is placed between two letters, each of greater value, its value is taken from the sum of the other two. Thus, XIV=14, XXIX=29, XCIV=94.

5. A bar or dash placed over a letter increases the value a thousand times. Thus, V with a line over it ezuals 5,000; L with a line over it equals 50,000.