00:01
We have a population with mean, mu equals 77, and we have the following sample data randomly selected from that population.
00:09
From this sample data, we want to calculate the sample mean and sample standard deviation.
00:14
So, remember that these terms are defined by the following formulas.
00:17
X bar sample mean is the sum of the data divided by n, or 71 .4.
00:22
And the sample standard deviation s is a sum of deviations about the mean squared, all divided by n minus 1, in this case, 20 .65.
00:29
Next, what we want to use a sample data to do is to implement a left -tailed test.
00:33
That is, we want to use the sample data to determine whether or not we have evidence that the population mean is less than the known mean of 77.
00:41
We'll use an alpha of 0 .05 as informed, and we want to make a note right now that we are told x is approximately normal to this distribution.
00:50
So to implement this test, we have to answer the following questions in order.
00:53
To start, what are the significance and hypotheses? we're told alpha equals 0 .05...