How is the probability of two mutually exclusive events calculated?

The probability of two mutually exclusive events is calculated by summing the individual probabilities of the events. If events A and B are mutually exclusive, they cannot occur at the same time. Therefore, their combined probability is simply the sum of their individual probabilities.

The correct calculation for the probability of either event A or event B occurring is represented mathematically as P(a or b) = P(a) + P(b). In this case, since the events are mutually exclusive, there’s no need to subtract any overlap (which is what P(ab) represents).

While the other choices provide formulas relating to probabilities, only the correct interpretation recognizes that for mutually exclusive events, the overlap (where both events could occur at the same time) is nonexistent, simplifying the calculation to the sum of the individual probabilities without needing additional terms. Hence, choice C expresses the appropriate relationship for mutually exclusive events correctly and highlights that no adjustment for overlap is necessary due to the nature of their exclusivity.