XIX
10 + 9 = 19
XIX breaks down as X + IX (X = 10, IX = 9), which add up to 19. It uses subtractive notation: IX (10 - 1).
XIX breaks down as X + IX (X = 10, IX = 9), which add up to 19. It uses subtractive notation: IX (10 - 1).
The number 19 is written XIX 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.