A researcher is interested in measuring the average satisfaction score (0 = lowest and 100 = highest) among patients using a particular medical device. She randomly samples 25 patients and finds the average satisfaction to be 55.4 with a standard deviation of 6.9. Assume that patient satisfaction follows a normal distribution. (a) Using the above data, construct a 95% CI for patient satisfaction with that medical device. 2. A formulation scientist is interested in comparing the dissolution rates of two alternative formulations of the same drug. The data is below: Formulation A: average dissolution = 85%; standard deviation = 4.2%; n =10 Formulation B: average dissolution = 78%; standard deviation = 4.8%; n =10 Test whether the difference between the means of the two groups is significant at a significance level of .05. (a) What are the null and alternative hypotheses? (b) Draw the picture of the distribution of the test statistic under H0. Include critical value(s) and region(s) of rejection. (c) What is the calculated value of the test statistic? (d) What is your conclusion? (e) Construct a 95% CI for the mean difference between dissolutions of formulations A and B. 3. QA specialist is interested in comparing the defect rates of tablets produced on two tablet presses TP-1 and TP-2. The data is below: TP-1: Out of 700 tablets tested, 84 have minor defects. TP-2: Out of 250 tablets tested, 23 have minor defects. Test whether the difference between the proportions of defects in the two groups is significant at an alpha level of .05. (a) What are the null and alternative hypotheses? (b) Draw the picture of the distribution of the test statistic (under H0). Include critical value(s) and region(s) of rejection. (c) What is the calculated (computed) value of the test statistic? (d) What is your conclusion? 4. A pharma company you work for makes jars with cream. It claims that the average amount of cream in a jar is at least 100 g. To prove that claim to the customers you decide to test the claim at a significance level (alpha) of .05. You randomly sample 25 jars of cream made by the company and find the sample mean to be 103.5 g with a sample standard deviation of 5.5 g. Now you need to analyze that data. (a) What are the null and alternative hypotheses you'll choose? Think about this - it is here that many students make an error! (b) Draw the picture of the distribution of the test statistic (under H0). Include critical value(s) and region(s) of rejection. (c) What is the calculated (computed) value of the test statistic? (d) What is your conclusion