1. The hourly sales of fried chicken at Louisiana Fried Chicken are normally distributed with mean 2000 pieces and standard deviation 500 pieces. What is the probability that in a 9-hour day more than 20,000 pieces will be sold?

2. A store manager designs a new accounting system that will be cost effective if the mean monthly charge account balance is more than $170. A sample of 400 accounts is randomly selected. The sample mean balance is $178 and the sample standard deviation is $65. Can the manager conclude that the new system will be cost effective?

(a) Carry out a hypothesis test to answer this question. Use the O = 0.05 level of significance.
(b) Compute the p-value of the test.

3. An econometric professor's rule of thumb is that students should expect to spend 2 hours outside of class on coursework for each hour in class. For a 3 hour per week class, this means that students are expected to do 6 hours of work outside class. The professor randomly selects eight students from a class, and asks how many hours they studied econometrics during the past week. The sample values are 1, 3, 4, 4, 6, 6, 8, 12.

(a) Assuming that the population is normally distributed, can the professor conclude at the 0.05 level of significance that the students are studying on average at least 6 hours per week?

(b) Construct a 90% confidence interval for the population mean number of hours. studied per week.

4. To evaluate alternative retirement benefit packages for its employees, a large corporation must determine the mean age of its workforce. Assume that the age of its employees is normally distributed. Since the corporation has thousands of workers a sample is to be taken. If the standard deviation of ages is known to be a = 21 years, how large should the sample be to ensure that 95% interval estimate of mean age is no more than 4 years wide?

1. The hourly sales of fried chicken at Louisiana Fried Chicken are...