And so we get a value of 00:25 or one four or equivalent to 25%, whichever way you want to actually look at it. Okay, so now that we have the product rule, let's actually move on to the sum rule. So let's take a look at what the sum rule tells us. 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.