课程名称： 统计学] 课程性质： 整开 课程范围： Chapters 7 and 8 开课教师： 丁兆平 开课学院： 商学院 开课系级： 统计系 考试日期(年月日)： 2013/12/19 考试时限(Mins)： 60 min 附注： 试题本文： 1. The time patrons at the Grande Dunes Hotel in the Bahamas spend waiting for an elevator follow a uniform distribution between 0 and 3.5 minutes. a. How long does the typical patron wait for elevator service? (10 pts) b. What is the standard deviation of the waiting time? (10 pts) c. What percent of the patrons wait for less than a minute? (10 pts) 2. At the downtown office of First National Bank, there are five tellers. Last week, the tellers made the following number of errors each: 2, 3, 5, 3, and 5. a. How many different samples of 2 tellers are possible? (5 pts) b. List all possible sample of size 2 and compute the mean of each. (10 pts) c. Compute the mean of the sample means and compare it to the population mean. (5 pts) 3. The Oil Price Information Center of greater Houston reports the mean price per gallon of regular gasoline is $3.00 with a population standard deviation of $0.18. Assume a random sample of 40 gasoline is select and their mean cost for regular gasoline is computed. a. What is the standard error of the mean in this experience? (10 pts) b. What is the probability that the difference between the sample and the population mean is less than 0.01? (10 pts) c. What is the likelihood the sample mean is greater than $3.08? (10 pts) 4. It is estimated that 65 percent of those taking the quantitative methods portion of the CPA examination pass that section. 80 students are taking the exam this Friday. What is the approximate probability that exactly 50 students will pass? (10 pts) 5. The time between visits to a hospital emergency room for a member of the general population follows an exponential distribution with a mean of 2.5 years. What proportion of the population will visit an emergency room next year, but not this year? (10 pts) --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 140.119.193.69 ※ 编辑: Inosxz 来自: 140.119.193.69 (01/16 18:30)