And for a discrete distribution like this, your mean or your expected value is just going to be the probability-weighted sum of the different values that your distribution can take on. Now, the way I've written it right here, you can't take a probability-weighted sum of u and f. You can't say 40% times u plus 60% times f. You won't get any type of a number. So what we're going to do is define u and f to be some type of value. So let's say that u is 0 and f is 1. And now the notion of taking a probability-weighted sum makes some sense. So the mean of this distribution is going to be 0.4. That's this probability right here.