00:01
In this problem, it is said that a random variable x is best described by a normal distribution with mu is 36 and sigma is 6, and we want to find the z score which corresponds to each of the given x values.
00:12
So recall the formula for the z score.
00:15
This is given by x minus mu divided by sigma.
00:18
Here, x is the raw score, mu is the mean, and sigma is the standard deviation.
00:24
So let us find our required z scores.
00:27
So first of all, we want the z score corresponding to x is 36.
00:31
Mu is 36, sigma is 6.
00:33
So we end up with 0 over 6, that is 0, and so our required z score is 0.
00:39
Now next, x is 42.
00:41
So we have 42 minus 36 divided by 6.
00:44
That will be 6 divided by 6, which is equal to 1.
00:48
And so our required z score is 1.
00:52
Now for the next one, the value of x is 47 .5.
00:56
So this is what we get.
00:59
So we have 11 .5 divided by 6, and this is, approximately equal to 1 .92...