And so that's how many sample standard deviations is it away from its mean. And so that's the z-score for that x data point, and this is the z-score for the corresponding y data point. How many sample standard deviations is it away from the sample mean? In the real world, you won't have only four pairs, and it will be very hard to do it by hand, and we typically use software, computer tools to do it, but it's really valuable to do it by hand to get an intuitive understanding of what's going on here. So in this particular situation, r is going to be equal to one over n minus one. We have four pairs, so it's gonna be one over three, and it's gonna be times a sum of the products of the z-scores. So this first pair right over here, so the z-score for this one is going to be one minus how far it is away from the x sample mean divided by the x sample standard deviation, 0.816, that times one, now we're looking at the y variable, the y z-score, so it's one minus three, one minus three over the y sample standard deviation, 2.160, and we're just going to keep doing that.