00:01
So for your question, i'm going to be able to help you out on these first two.
00:03
After this, don't put so many questions into one problem because that ends up taking too much time to do for one question.
00:11
So we have that the manufacturer says that they have an average of at least 20 ounces.
00:17
So that will be our assumption.
00:21
And alternately, that the mean is less than 20 ounces.
00:24
And we have the standard deviation is given to us as 0 .4 ounces with the sample size of 16 and they got an x -bar for that of 19 .675 and so our this is going to be a z test and our z value will be to take that x -bar minus the 20 divided by the population standard deviation over the square root of 16 and so let's quickly put that in as that z test i'm using my software and we have the mean the standard deviation the x bar will put in as nineteen point six seven five and our sample size is that sixteen and they do tell us that this is a normal distribution and that is important because our sample size is relatively small and and we're doing a z test because the population standard deviation is known and this z value comes out to be negative 3 .25 and the p value for that left tail test is equal to 0 .00058 and this is less than your significance level of 10 % so we have evidence to reject the null and say there is sufficient evidence that the the mean is less than 20 ounces.
01:55
So it's not what they say.
01:57
Now i'll go through and work on this second one too.
02:01
You would be assuming that the proportion, they say that if it exceeds 7 .5%, this is a proportion test, so if it's greater than .075, if they don't comply, then they are going to decide not to buy these and if it's less than or equal to that they will buy so they will buy here they will not buy and they have a sample and they find that 1095 let me look at a bigger screen 1095 out of 1200 1095 comply out of 1 ,200...