So the probability of two or more mutually exclusive events occurring is equal to the sum of their individual probability. So unlike here, here we're not going to multiply, we're going to add those probabilities up. And unlike in this event that deals with independent events, unlike in this rule that deals with independent events, in this rule we deal with something called mutually exclusive rules or mutually exclusive events. So what exactly do we mean by mutually exclusive events? Well, two events are set to be mutually exclusive if one event taking place will prevent the second event from actually taking place. So two events are set to be mutually exclusive if the occurrence of one of those events prevents the other event from actually taking place.