1) Understanding Mean and Standard Deviation (6p) a. Which normal curve has a greater mean? b. Which normal curve has a greater standard deviation? Percent 2) Properties of Normal Distribution: (6p) Short Answer: Write the word or phrase that best completes each statement or answers the question. a. What is the total area under the normal curve? b. The normal distribution is dened by two parameters. What are they? c. What are the mean and standard deviation of the standard normal distribution? True/false Questions: Decide whether the following statements are true or false. (6p) a. The mean and median of a normal distribution are equal. b. A z-score represents the number of standard deviations above or below the mean. c. The mean of the sampling distribution of the means is equal to the mean of the population from which the values were sampled. Each of the following statements contains an error. Describe the error and then correct the statement. (28p) 3) 4) a. When taking SRSs from a large population, larger sample sizes will result in larger standard deviations of x. b. For an SRS from a large population, both the mean and the standard deviation of x depend on the sample size n. c. The central limit theorem states that for large n, the population mean In is approximately Normal. (1. For large n, the distribution of observed values will be approximately Normal. e. A density curve is a mathematical model for the distribution of a categorical variable. f. The area under the curve for a density curve is always greater than the mean. g. If a variable can take only negative values, then the density curve for its distribution will lie entirely below the x axis. Business employees. There are more than 7 million businesses in the United States with paid employees. The mean number of employees in these businesses is about 16. A university selects a random sample of 100 businesses in Colorado and nds that they average about 11 employees. Identify the bold numbers a parameter or a statistic? (4p) At a recent W conference, Nielsen reported an average of 41 apps per smartphone among U.S. smartphone subscribers. State the population and the statistic for this survey. (6p) 8) Supplier ontime delivery performance is critical to enabling the buyer's organization to meet its customer service commitments. Therefore, monitoring supplier delivery times is critical. Based on a great deal of historical data, a manufacturer of personal computers nds for one of its justintime suppliers that the delivery times are random and well approximated by the Normal distribution with mean 51.54 minutes and standard deviation 9.4 minutes. (18p) a. What is the probability that a particular delivery will exceed one hour? I). What is the probability that a particular delivery arrives in less than one hour? c. What is the probability that the mean time of ve deliveries will exceed one hour