00:01
All right, for this problem, we have that our sample size, oh, let me change my color here, our sample size, n, is equal to 350.
00:10
Our sample mean value, x bar, is equal to 8 ,965, and our sample standard, or, pardon me, not sample standard deviation, our population standard deviation, is given to us as 1 ,200.
00:25
Now, because we know the population standard deviation, the appropriate test statistic here is going to be a z score, where z is equal to our sample mean value minus the null hypothesized mean value divided by population standard deviation over the square root of the sample size.
00:46
Now, our null hypothesis is going to be that the mean value is equal to the claimed value of 8 ,700, and we're told that a financial administrator believes that the average cost is higher.
01:04
So our null hypothesis, or our alternate hypothesis rather, is that the mean value is greater than 8 ,700.
01:11
So this is going to be a one -tailed test.
01:15
Our test statistic here, zd knot, is going to then be given by 8 ,965 minus the null hypothesized value, 8 ,700, divided by standard deviation, 1200, over the square root of sample size 350...