 Hi, folks. This is Dr. Don. I have a problem out of Chapter 7 where we're doing single sample test of apothesis. Now this particular problem is about a politician claiming that the mean salary for managers in his state is more than a national meat of any 2000. You should pick up pretty quickly that that is the claim because it says the politician claims. And in that claim is this critical phrase there is more than. More than is, of course, a greater than symbol, which is a form of inequality, therefore that means this claim is the alternative apothesis. We're given the population standard deviation of $8,400. And in our course and in many intrastats courses when you're given the population standard deviation, Sigma, that means you use the Z distribution. We're given the significance level of .01 and asked to test the claim. We're given a lot of raw data there. Remember, if you're in my stat lab, you can click on the little blue triangle over here and open this data directly in stat crunch, Excel, or you can copy it and paste it where you want. I'm going to open it in Excel. Okay. I have Excel open. I've got the data in column D over here and I've entered some information. The assumed population mean mu is $82,000. Sigma is $8,400. Alpha is .01. We've got the null and the alternative stated. I always think that's important to do. The alternative is that the mean is greater than $82,000 as the claim. Here's the sketch that I think you should always draw. Remember, we had a normal distribution for the population whose mean is $82,000. Because this is a right tail test, the alternative is the claim with pointing to the right, that means our X bar is probably over here on the right side and we need this area in the right tail. Now, we're going to use stat crunch to do it. I'm going to go over here to the menu. I've got stat crunch install and I've got a video showing you how to do that. I'm going to look over here. We want a one sample test and in the dropdown, we want the Z test for the mean, sigma known, which is exactly what we want. Brings up a dialog box. Our null hypothesis is $82,000. Our level of significance is .01. The standard deviation of the population, $8,400. Now we don't know the summary statistics, but we have the raw data. We click there. We don't have a label in the first cell. I'm going to click in that box and then I'm going to highlight my data. Now, down here, we need to select the options. This is an upper tail test and I'm not going to worry about labeling. I'm going to click OK and PHTAT gives us the solution here. It gives us a new worksheet that it enters. There's our data again, $82,000 for the mean, alpha .01, sigma $8,400, sample size of 30, sample mean X bar 84, 439. We get the standardized test statistic 1.59 and they give us a critical value, which we don't need because we're going to use the p-value approach. But in both cases, you can see that the standardized test statistic is less than the upper critical value. Therefore, that means it's non-significant and we would fail to reject. And of course, our p-value is .056, which is much greater than our alpha .01. So again, that tells us we failed to reject the null. PHTAT is a pretty handy tool to get. I would recommend you try it out. Hope this helps.