00:01
To begin, i'll note here that since we have n greater than 30, we have that the distribution of x -bars will be approximately normal by the central limit theorem.
00:21
Then we'd have that for not part b yet.
00:26
We'd have that the mean value of our x -bars should be equal to the mean value of the population, 89, and the standard deviation of the x -bars is going to.
00:35
To be equal to the standard deviation of the population divided by the square root of the sample size.
00:41
So sigma x bar will be equal to three.
00:44
Then for part b, c, and d, what i'll do is bring up a website called salt, which is quite useful for these sorts of problems.
00:57
So we'll go to distribution calculators.
01:00
We want to set our mean value to 89.
01:03
Oops, mean is 89, and our standard deviation for the samples will be three...