00:01
Hi, i'm david and i'm hedg.
00:02
Have you answered your question? in the question here, we are going to discuss about the sambole distribution of the sample mean.
00:08
Let me remind you about the central limit theorem.
00:12
It says that if we have the symbol size n, at least the 30, and then the symbol mean x -bile would be approximately to the normal.
00:20
In such a way, then the mean of the x -bore equal to the mean and the population, standard division x -bore equal to the sigma over -scoling to the n.
00:28
And if we tend the x bar, we minus the mean over the standard deviation, we obtain the standard no more.
00:35
In the equation here, we have the median equal to the 23100 ,000, and then we have the mean -mule equal to the 232 ,700, and we have the standard division equal to the 80 ,000.
00:58
And we have the symbol size n equal to the 100, so it's greater than 30 already.
01:04
Now in the question a, if we have n equal to 100, describe the cell of the x bar.
01:10
So x bar will follow by the normal because n greater than 30, when the mean of the x bar equal to the mean of the population equal to the 27270, standard division x bar equal to the sigma overscor to the n equal to the 18.
01:28
1st000 divided square into the 100 and equal to the 8 ,000 now for the question therefore the answer for this one it will be approximately to the normal so therefore the answer will be the b now for the question b when you find the probability that the same will be less than 290 ,000 to find this probability i need to convert the expanse into the z to do it i need to apply this formula here.
02:05
Then it will take the $290 ,000.
02:09
We minus the mean will be the 27270 divided by the standard deviation will be the 8 ,000.
02:17
Then it will compute...