Question 1: The following data set represents the repair costs (in dollars) for a random sample of 30 dishwashers

1. Find the point estimate of the population mean.
2. Find the margin of error for a 95% level of confidence.
3. Construct a 95% confidence interval for the population mean and interpret the results.
   Question 3: The following data set represents the time (in minutes) for a random sample of phone calls made by employees at a company:
   
   (b) Find the sample standard deviation.
   (c) Use the t-distribution to construct a 90% confidence interval for the population mean and interpret the results. Assume the population of the data set is normally distributed.
4. Repeat part (c) assuming that \(\sigma =3.5\). Compare results.

Question 25: "The standard deviation of the base price of a certain type of car is no more than $1220."

Question 32: ER Visits. "A hospital spokesperson states that 2% of emergency room visits by college undergraduates are for alcohol-related health problems."

Question 37: Lung Cancer. "A government report claims that the proportion of lung cancer cases that are due to smoking is 90%"

Question 33: In Illinois, a random sample of 85 eighth grade students has a mean score of 265 with a standard deviation of 55 on a national mathematics assessment test. This test result prompts a state school administrator to declare that the mean score for that state’s eighth graders on the examination is more than 260. At \(\alpha =0.04\), is there enough evidence to support the administrator’s claim?

Question 35: A tea drinker’s society estimates that the mean consumption of tea by a person in the United States is more than 7 gallons per year. In a sample of 100 people, you find that the mean consumption of tea is 7.8 gallons per year with a standard deviation of 2.67 gallons. At \(\alpha =0.07\), can you support the society’s claim?

Question 42: In your work for a national health organization, you are asked to monitor the amount of sodium in a certain brand of cereal. You find that a random sample of 52 cereal servings has a mean sodium content of 232 milligrams with a standard deviation of 10 milligrams. At \(\alpha =0.04\), can you conclude that the mean sodium content per serving of cereal is less than 230 milligrams?

Question 47: You believe the mean annual kilowatt usage of U.S. residential customers is less than 10,800. You do some research and find that a random sample of 30 residential customers has a mean kilowatt usage of 10.700, with a standard deviation of 280. You conduct a statistical experiment where \({{H}_{0}}:\mu \ge 10,800\) and \({{H}_{A}}:\mu <10,800\). At \(\alpha =0.01\), explain why you cannot reject \({{H}_{0}}\).

Question 5: In a survey of 1037 adults from the United States age 65 and over, 643 were concerned about getting the flu.

1. Find a point estimate for the population proportion \(p\) of those concerned about getting the flu.
2. Construct 90% confidence interval for the population proportion.
3. Find the minimum sample size needed to estimate the population proportion at the 99% confidence level in order to ensure that the estimate is accurate within 4% of the population proportion.

Question 6: Refer to the data set below. Assume the population of dishwasher repair cost is normally distributed.

1. Construct a 95% confidence interval for the population variance.
2. Construct a 95% confidence interval for the population standard deviation.

Price: $27.91

Solution: The downloadable solution consists of 15 pages, 1291 words and 4 charts.
Deliverable: Word Document