And if that doesn't make sense to you, this is essentially just saying that what is the probability that y is greater than 1.9 and less than 2.1? These two statements are equivalent. I'll let you think about it a little bit. But now this starts to make a little bit sense. Now we have an interval here. So we want all y's between 1.9 and 2.1. So we are now talking about this whole area.