PCO stands for Potential Change Order (construction management). Suggest new definition. This definition appears somewhat frequently and is found in the following Acronym Finder categories: 1  Business, finance, etc.
Quick Answer. The Roman numeral XIX is the number 19. X is the number 10, and I is the number one. When a lower number is placed in front of a larger number, it indicates subtraction; IX is the same as 10 minus one, which equals nine. The Ancient Romans used different letters to represent numbers.
If number XL is within to text or sentence it should be read in its equivalent in arabic numbers, in this case 40. XXXIX is number 39. XLI is number 41. Calculate the conversion of any number and its equivalent in roman numerals with our roman numerals converter.