Roman numerals · Year 6
In Year 6 you learn: years written in Roman numerals.
Roman numerals are the number system of ancient Rome, still seen on clocks, in book chapters, film credits and the names of kings and queens. Seven letters are added together, but a smaller letter in front of a bigger one is taken away instead.
Key facts
- I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1,000.
- Letters are usually written biggest first and added: LXVI = 50 + 10 + 5 + 1 = 66.
- A smaller letter before a bigger one is subtracted: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.
- Never more than three of the same letter in a row: 4 is IV, not IIII.
- Convert a number one place value at a time: 1,994 = M + CM + XC + IV = MCMXCIV.
Worked examples
Example 1
What number is XXVII?
Answer: 27
Example 2
Write 49 in Roman numerals.
Answer: XLIX
Example 3
A building says it was finished in MCMLXXXIV. What year is that?
Answer: 1984
Example 4
Work out CXL − LXV. Give the answer in Roman numerals.
Answer: LXXV