Branching for state specific slides

I'm building a large Storyline course that involves various US states. The user clicks the state they are in (such as California) and the corresponding slides for that state should show up. Here is my question...most of the slides for all the states are the same except for a few. How can I build the branching of the course where, for example, a California user doesn't see a particular slide(s) but does see the rest of the in-common state slides. I don't want to duplicate the in-common slides for each state and create this one massive course just because of a few slides. Is there a way...I'm pretty new at branching so please use layman's terms