00:01
The population mean and standard deviation were given here.
00:04
So the population mean denoted by mu, which is 500, and the population standard deviation denoted by sigma, which is 600 here.
00:12
Let me define the random variable x.
00:14
We have a normal distribution here, so the mean is 500, the standard deviation 100.
00:19
So we have to find the top 2%.
00:22
Let me draw a normal distribution graph here.
00:26
So let's say we have the lowest value of x1 and the area of this region, which is 2%, so i can write that as 0 .02.
00:34
In order to get the x1 here, what do i need? i need the area to the left of this x1, and we know that the total area under the curve, which is 1.
00:43
So first of all, let's express this green shaded region, where the random variable x, which is less than x1, total area 1 minus the excluded part, which is 0 .98...