I know that commonly, the roman numerals are used to refer to a date or, more precisely, to a specific century, like in the examples below:
- Aconteceu no século XX;
- Um dos livros mais importantes do século XVIII;
I'd like to know if there is some rule to use this type of number in portuguese. They are only allowed to talk about a century or this is just a convention?
Can I use it to say something like
Eu tenho X anos. or not?