Formal:
* Las tres de la tarde: This is the most formal and common way to say "three pm". It literally translates to "the three of the afternoon".
Informal:
* Las tres de la tarde: This is also acceptable in informal contexts.
* Las tres: This is a more informal way to say "three pm", but it's important to be sure that the context makes it clear that you're referring to the afternoon.
Other options:
* Tres de la tarde: This is another option, although it's not as common as "las tres de la tarde."
Important Note: In Spanish, it's essential to use the feminine form of "tres" (three) when referring to a specific time. So, you always say "las tres" and not "los tres."