Station 3: ______
1. A sample of Alzheimer’s patients are tested to assess the amount of time in stage IV sleep. It has been hypothesized that individual suffering from Alzheimer’s Disease may spend less time per night in the deeper stages of sleep. Number of minutes spent in Stage IV sleep is recorded for 61 patients. The sample produced a mean of 48 minutes and a population standard deviation of 14 minutes of stage IV sleep over a 24 hour period of time. Compute a 95% confidence interval for the average amount of time in stage IV sleep. Then, interpret your results.
2. A university wants to know more about the knowledge of students regarding international events. They are concerned that their students are uninformed in regards to news from other countries. A standardized test is used to assess students’ knowledge of world events. A sample of 30 students is tested and have a sample mean of 58. It is known that the population standard deviation =5. Compute a 99 percent confidence interval based on this sample's data for the average score on an assessment of world events. Then, interpret your results.
3. Consider the following exercise: The inspection division of the Lee County Weights and Measures Department is interested in estimating the actual amount of soft drink that is placed in 2-liter bottles at the local bottling plant of a large nationally known soft-drink company. The bottling plant has informed the inspection division that the population standard deviation for 2-liter bottles is 0.05 liter. A random sample of one hundred 2-liter bottles obtained from this bottling plant indicates a sample average of 1.99 liters. Set up a 95% confidence interval estimate of the true average amount of soft drink in each bottle.
Station 2: ______
1. The high temperature of the day in Augusta is recorded for every day in November since 1931, and this data forms a normally distributed population. Its mean is 74 degrees with a standard deviation of 6.75. Suppose the mean temperature for the 30 days in November 2010 is 72 degrees. What is the probability that a random sample of 30 days in November will have an average temperature of 72 degrees or lower?
2. All students at LHS who use Facebook are being observed, and the amount of time each spends daily on the site is placed in a data set that is normal. Its mean is 24 minutes with a standard deviation of 8. If ten random students are selected from LHS, what is the probability the average amount of time they spend on the site is between 20 and 25 minutes?
Station 1: ______
1. All students’ grades on the Nine Weeks Test in Math 2 can be placed in a normal data set, with a mean of 72 and a standard deviation of 11. What percentage of students passed the test (scored 70 or higher)?
2. A patient recently diagnosed with Alzheimer's disease takes a cognitive abilities test. The patient scores a 47 on the test (mean = 52, standard deviation of 5). What is this patient's percentile rank?
3. Another patient with Parkinson's disease takes the same cognitive abilities test as in the question above and scores an 54. What percent of individuals would receive higher score?
4. Pat and Chris both took a spatial abilities test (mean = 80, S = 8). Pat scored a 76 and Chris scored a 94. What percent a individuals would score between Pat and Chris?