Roman Numerals

Roman Numerals are the letters used by the Roman Empire to show numeric values.

• I = 1
• V = 5
• X = 10
• L = 50
• C = 100
• D = 500
• M = 1000

Large Numbers

To write large numbers, like for instance five thousand, Romans would not use MMMMM. Rather, they would write V and put a bar over it. A bar over a letter represents one thousand times that letter.

Subtraction

Letters are put in order from greatest to least. A lesser letter occurring before a greater letter is subtraction. When subtracting, only subtracting powers of ten such as I, X, or C is allowed. You cannot subtract with V, for example. Too, you can only subtract one digit away. For example, IIX is not 8 but rather use VIII for 8. Finally, you cannot subtract one letter from another letter if it is ten times greater than it, so one would not be able to subtract X from M since M is one hundred times greater than X, yet you can subtract X from either L or C. In Roman times, while any combination of numerals which makes the appropriate number was considered sufficient, only the above method was considered proper.

• Example: MCMLXXXIII = 1983
• Example: MCC = 1200

Modern Use

While the Arabic system has become the standard contemporary numeral system, Roman numerals are still used today in limited settings. They express dates on building cornerstones or denote an epoch in art or literature. They also count installments in a series, such as movie sequels, the Super Bowl, the Ultimate Fighting Championship, or the Olympics.