00:01
In this question, you look at newborn babies, right? and according to the question, the weights of a newborn baby follows a normal distribution, and that has a mean of 7 .5 points and a standard variation of two points, right? and a group of pediaturitians want to implement special treatments for new born babies in the bottom 25 % both weight.
00:24
So you ask you to find a weight of babies.
00:27
Are there in a case they need some spatial treatment? so, you basically look at this x, right? this x follows a normal distribution, which is very shaped like this, and this is 7 .5.
00:38
You look at a value which you want to find, which i call x0, and below which, you know, there's a percentage of 25%, right? so you can find this x0, sometimes it's called 25th percentile, right? so that x0 can be found from the z score at 25th percentile.
00:58
So the z score at that is given by z, 25%...