With all the scenario based question the formula section can seem a bit daunting and there seems to be so many of them.
The approach I used it try to know the basics well, and how they are used in EVM, do a few questions and when you are comfortable with the concepts then start thinking of drilling down to the more complicated ones.
The thing about the formula section you never quite know how complex the question will be, you may get an easy one and therefore be glad you know the basics, or it could be a very complex one and you may struggle in the time. As many have already said, its likely you will only get a handful of these questions, it is worth knowing them as they often come up in interviews, but its about breaking them down so they don't seem too overwhelming.