A guide to the rules of Roman Numerals.Materials
- Explain to your child that the number symbols we use every day came from Arabia and are called Arabic numerals. A different system was used in ancient Rome. We call these symbols Roman numerals. The Roman numeral system uses six basic symbols: I (one), V (five), X (ten), L (fifty), C (one hundred), and M (one thousand). There are two rules for writing Roman numerals:
- Putting a numeral of lesser value before a numeral of greater value decreases the second numeral by the amount of the first. Thus IV equals four because V (five) is decreased by I (one).
- Putting a numeral of lesser value after a numeral of greater value increases the first numeral by the amount of the second. Thus VI equals six because V (five) is increased by I (one).
- Write some Roman numerals on a sheet of paper and challenge your child to figure out what numbers they represent. Start with easy ones, such as I (one), II (two), III (three), IV (four), V (five), VI (six), VII (seven), VIII (eight), IX (nine), and X (ten). When your child masters these numbers, try more difficult ones, such as XL (forty), LX (sixty), XC (ninety), and so on.
- Take turns writing and interpreting Roman numerals.