Firstly I wanted to ask for this question how can probability of a and b add up to more then one. If this happens then are they saying the two events do not belong to the same sample space because that's the only way that their probabilities can add up to more than 1 I think.
Also, if we have two different events from two different experiments is it possible for us to compare them e.g to see if they are independent. E.g let one experiment be rolling a die once and another experiment be tossing a coin. Then if we choose an event from experiment 1 and an event from experiment two is it possible for us to compare the independence of those two events? (Although they would be independent anyways.)
Sorry if this seems like a stupid question.