 Hi, this is Dr. Don. I have a problem out of Larson chapter two on descriptive statistics. We're given the information about heights of men on a baseball team. We're told that they have a bell shaped distribution, which should be a clue that this is a normal distribution. We're given the distributions mean of 181 centimeters and a standard deviation of nine centimeters. And we're asked to use the empirical rule to find the approximate percentage between these two sets of values. Remember the empirical rule is also known as the 689599.7 rule. But what we're talking about is that 68% of the data are the values in a bell shaped distribution or normal distribution are found between minus one and plus one standard deviations. 95% between minus two and plus two standard deviations and 99.7 within minus three and plus three. Now you can use that information in your calculator to find these probabilities. But I would recommend that you learn to use stat crunch calculators to do this kind of problem. Remember you can go to the question help if you're in my stat lab, click on that and then open up stat crunch from there. Once you're in stat crunch, you just go to stat calculators normal and we open up the normal calculator. When it opens it comes up with the standard normal distribution which has a mean of zero and a standard deviation of one. Here we're given a mean of 181 so we enter that and a standard deviation of nine centimeters we enter there. So before we click compute, let's click on the between button because we're given two values and we need to enter those one, six, three, one, nine, nine and then we click compute and we get an answer of 0.954. That's the area in red under the normal distribution or the bell shaped distribution. 95.4% of the data is found in that red area between these two values. Then we just enter the final two values 154, 208. Click compute and we see we get our 99.7% in that red area. One final thing I'll show you just to solidify the empirical rules, we put back our standard normal mean of zero and standard deviation of one and we put in minus three standard deviations and plus three standard deviations and click compute we get 99.7 which we should and that confirms the normal distribution follows the empirical rule. Hope this helps.