So we have a 3 8th chance of getting exactly 2 heads. Now, that's kind of what we've been doing in the past. But what I want to do is think about a way so we wouldn't have to write out all the possibilities. And the reason why that's useful is we're only dealing with 4 flips now. But if we were dealing with 10 flips, there's no way that we could write out all the possibilities like this. So I really want a different way of thinking about it. And the different way of thinking about it is if we're saying exactly 2 heads, you can imagine we're having the 4 flips.