It’s weird because Switzerland is one of the most armed countries in Europe, as in they have firearms but barely any shootings of any kind (so you don’t often hear news equivalent to a guy shooting students in a classroom or killing people at a shopping mall over there). Part of it has to do with the draft (most people who purchase firearms have a form of training, as they learnt how to properly handle them during military service).
You’re correct, in one my edits before submitting I must have erased the 100 there and forgot to move the decimal place, thanks for pointing it out (I’ve edited my post). The rest of the math was done considering the correct number, i.e. 1.2 weapon per person, it was just a wording mistake.