The Roman Numeration System

The Romans used letters of the alphabet as numerals.

Q1.   Convert DCLXXVIII to Hindu-Arabic notation.

Furthermore, if the value of a numeral is ever less than the value of the numeral to its right, then the value of the left numeral is subtracted from the value of the numeral to its right. For example:

  • IV represents 5 – 1 = 4
  • IX represents 10 – 1 = 9
  • XL represents 50 – 10 = 40
  • CM represents 1000 – 100 = 900

There are two restrictions on this subtraction principle:

  1. We can only subtract the numerals I, X, C, and M. For example, we cannot use VL to represent 45.
  2. We can only subtract numerals from the next two higher numerals. For instance, we can only subtract I from V and X; therefore, we cannot use IC to represent 99.

Q2.   Convert MCMXLIII to Hindu-Arabic notation.

Q3.   Write 492 in Roman numerals.

In the Roman system:

  • A bar above a symbol means to multiply the value by 1,000.
  • Bracketing a symbol with two vertical bars multiplies the value by 100.

Q4.   Convert 


 to Hindu-Arabic form.

Q5.   Convert 32 400 to Roman Numerals.