In Roman numerals, what does the letter 'X' represent?

The letter 'X' in Roman numerals represents the value of 10. This is part of a system where specific letters correspond to certain values: for instance, 'I' stands for 1, 'V' for 5, 'X' for 10, 'L' for 50, 'C' for 100, 'D' for 500, and 'M' for 1000. Understanding Roman numerals is important not only for historical context but also for various applications in fields such as nursing, where you might encounter them in dosage measurements or when referencing specific timelines.

The other values associated with the options—5, 15, and 20—are represented by other combinations of letters in the Roman numeral system. For example, 5 is denoted by 'V', while 15 is expressed as 'XV' (10 + 5), and 20 is shown as 'XX' (10 + 10). Recognizing these values helps solidify comprehension of how the Roman numeral system operates as a whole.