More Practice Review questions prior to big exam:

2. Cigarette Costs In an American Express survey of 1000 adults 18 and older, 62% said that cigarettes should cost more to help offset potential negative health effects. Use the sample data to construct a 95% confidence interval estimate of the percentage of all adults who share that same belief. What can we conclude about a claim that half of all adults share that same belief? 3. ICU Patients Listed below are the ages of randomly selected patients in intensive care units (based on data from "A Multifaceted Intervention for Quality Improvement in a Net- work of Intensive Care Units," by Scales et al., Journal of the American Medical Association, Vol. 305, No. 4). Find the mean, median, and standard deviation. Based on the results, is an age of 16 years unusual? Why or why not? 38 64 35 67 42 29 68 62 74 58 4. ICU Patients Use the sample of ages from Exercise 3 to construct a 95% confidence interval estimate of the mean age of the population of ICU patients. Do the confidence interval limits contain the value of 65.0 years that was found from a sample of 9269 ICU patients