XXIX
20 + 9 = 29
XXIX breaks down as XX + IX (XX = 20, IX = 9), which add up to 29. It uses subtractive notation: IX (10 - 1).
XXIX breaks down as XX + IX (XX = 20, IX = 9), which add up to 29. It uses subtractive notation: IX (10 - 1).
The number 29 is written XXIX in Roman numerals. Roman numerals use seven letters — I (1), V (5), X (10), L (50), C (100), D (500) and M (1000) — combined from largest to smallest, with subtractive pairs such as IV (4) and IX (9). Need another number? Use the Roman numeral converter or see the 1–100 chart.