I think this might be too easy compared to other questions on this site but I really can't find the solution.
60% of students passed class A 70% of students passed class B 80% of students passed at least one of both classes
a. What % of students passed both classes?
b. What % of students passed class A but failed class B?
I actually have the answers for both questions but no idea how to get there (a: 50% and b: 10%). Also, if anyone has a link to some theory about this kind of problems or more similar exercises I'd appreciate that a lot! Not sure how to look this up.
And another question (but I am not sure if I have all the numbers necessary for this one): If 51.8% of population has obesity and 48% of the population are male,.... what % of the male population has obesity if there's 10% more females (than males) without obesity? Can this be solved with these numbers? I might have forgotten some part of the question so I'm not sure about this one.