They thought it was a good tool. They thought that the computers were a good tool. We'll just define a zero value as a teacher that says not good. Some proportion of the total teachers think that it is a good learning tool. That proportion is P. The rest of them think it's a bad learning tool. 1 minus P. We have a Bernoulli distribution right over here. We know that the mean of this distribution, or the expected value of this distribution, is actually going to be P. It's actually going to be a value.