And when I talk about this extreme, it could be either a result less than this or a result that extreme in the positive direction, more than three standard deviations. So this is essentially, if we think about the probability of getting a result more extreme than this result right over here, we're thinking about this area under the bell curve, both in the negative direction or in the positive direction. What is the probability of that? Well, we know from the empirical rule that 99.7% of the probability is within three standard deviations. So this thing right here, you could look it up on a z-table as well, but three standard deviations is a nice clean number that doesn't hurt to remember. So we know that this area right here, I'm doing in this reddish orange, that area right over there is 99.7%. So what is left for these two magenta or pink areas?