write zero in roman numeral.

There is no 0 in Roman numerals. The word nulla was used in medieval times to mean nothing or zero.

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To write zero in Roman numerals, you need to understand that the Romans did not have a symbol specifically for zero. Zero as a concept was not commonly used in ancient Rome.

The Romans primarily used seven basic symbols to represent numbers:

- I for 1
- V for 5
- X for 10
- L for 50
- C for 100
- D for 500
- M for 1000

Since zero was not part of the Roman numeral system, there is no direct representation for it. However, there is a Latin phrase, "nulla," which means "none" or "no value." In some cases, this phrase is used to indicate the lack of a value in Roman numeral inscriptions. However, it is important to note that "nulla" is not a standardized or universally accepted representation.

So, in short, there is no official Roman numeral representation for zero.