Truthfully, this is a homework problem. I've come across a solution, but I'm really trying to figure out how this works, hopefully at an intuitive level.
We have four events, A, B, C and D, and we are trying to find the probability that exactly one event occurs.
I've seen the "Inclusion exclusion principle", and that would help if I had to find the probability of A or B or C or D. I feel this should be trivial, probability is my weakest math, which is why I'm taking it, but this particular problem is giving me a lot of trouble. Any help would be greatly appreciated.