So now we have accounted for 0. Asked 3 years, 8 months ago. Another way to think about it. You must label them before you consider how they landed. We then count the total number of "ones" equals 2. What is the chance of throwing HHH? It doesn't matter which order the coins were tossed in, or even how we reordered them afterwards. For example, the permutations are not always neatly equally likely as we have in these constructed problems. GodlyHedgehog GodlyHedgehog 1 2 2 bronze badges.