There are different formulas for calculating the two types of compound events: Say A and B are two events, then for mutually exclusive events: P(A or B) = P (A) + P(B). For mutually inclusive events, P (A or B) = P(A) + P(B) - P(A and B).
determining the possibilities of a compound involves finding the sum of the probability of the individual event and if necessary removing any overlapping probabilities an exclusive compound event is one in which the multiple events do not overlap.
