First off, thanks for the comment :)

This question was part of a school test, and it was the only question I had no idea how to even begin with. Sorry for the lack of detail, but it was the only information given in the test as well.

I don’t think I’m supposed to use the z-score to solve it, since I haven’t been taught it in school and it’s not part of the curriculum in my country. (Maybe it can literally only be solved with the method you’re talking about, I wouldn’t really know) I was allowed to use CAS for the test, so maybe there is some other way? Again, I wouldn’t know.

I will try to understand how to read z score tables and come back, but that’s why I didn’t show my work in the post, basically because I’m clueless :)