The method of tree-ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population of x values has an approximately normal distribution. 1,292 1,292 1,229 1,285 1,268 1,316 1,275 1,317 1,275 LO USE SALT (a) Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to four decimal places.) X = 1283.2222 A.D. S = 26.6448 yr (b) When finding an 90% confidence interval, what is the critical value for confidence level? (Give your answer to three decimal places.) What is the maximal margin of error when finding a 90% confidence interval for the mean of all tree-ring dates from this archaeological site? (Round your answer to the nearest whole number.) E = Find a 90% confidence interval for the mean of all tree-ring dates from this archaeological site. (Round your answers to the nearest whole number.) lower limit A.D. upper limit A.D.The method of tree-ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population of x values has an approximately normal distribution. 1,271 1,243 1,229 1,257 1,268 1,316 1,275 1,317 1,275 LO USE SALT (a) Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to four decimal places.) X A.D. S yr (b) Find a 90% confidence interval for the mean of all tree-ring dates from this archaeological site. (Round your answers to the nearest whole number.) lower limit A.D. upper limit A.D. Need Help? Read It Watch ItHow much does a sleeping bag cost? Let's say you want a sleeping bag that should keep you warm in temperatures from 20F to 45 F. A random sample of prices ($) for sleeping bags in this temperature range is given below. Assume that the population of x values has an approximately normal distribution. 95 115 100 65 40 115 30 23 100 110 105 95 105 60 110 120 95 90 60 70 LA USE SALT (a) Use a calculator with mean and sample standard deviation keys to find the sample mean price x and sample standard deviation s. (Round your answers to four decimal places.) X = $ S = $ (b) Using the given data as representative of the population of prices of all summer sleeping bags, find a 90% confidence interval for the mean price # of all summer sleeping bags. (Round your answers to two decimal places.) lower limit upper limit LAHow much do wild mountain lions weigh? Adult wild mountain lions (18 months or older) captured and released for the rst time in the San Andres Mountains gave the following weights (pounds): 71 107 127 128 60 64 USE SALT Assume that the population ofx values has an approximately normal distribution. (a) Use a calculator with mean and sample standard deviation keys to nd the sample mean weight E and sample standard deviation 5. (Round your answers to four decimal places.) E = lb E (b) Find a 75% condence interval for the population average weight ,1; of all adult mountain lions in the specied region. (Round your answers to one decimal place.) lower limit E lb upper limit E lb Do you want to own your own candy store? Wow! With some interest in running your own business and a decent credit rating, you can probably get a bank loan on startup costs for franchises such as Candy Express, The Fudge Company, Karmel Corn, and Rocky Mountain Chocolate Factory. Startup costs (in thousands of dollars) for a random sample of candy stores are given below. Assume that the population of x values has an approximately normal distribution. 94 171 130 99 75 94 116 100 85 USE SALT (a) Use a calculator with mean and sample standard deviation keys to nd the sample mean startup cost; and sample standard deviation 5. (Round your answers to four decimal places.) thousand dollars ,7 =: s = E thousand dollars (b) Find a 90% condence interval for the population average startup costs ,u for candy store franchises. (Round your answers to one decimal place.) lower limit thousand dollars upper limit E thousand dollars Over the past several months, an adult patient has been treated for tetany (severe muscle spasms). This condition is associated with an average total calcium level below 6 mg/dl. Recently, the patient's total calcium tests gave the following readings (in mg/dl). Assume that the population of x values has an approximately normal distribution. 9.30 8.60 10.90 9.10 9.40 9.80 10.00 9.90 11.20 12.10 LA USE SALT (a) Use a calculator with mean and sample standard deviation keys to find the sample mean reading x and the sample standard deviation s. (Round your answers to four decimal places.) X = mg/dl S mg/dl (b) Find a 99.9% confidence interval for the population mean of total calcium in this patient's blood. (Round your answer to two decimal places.) lower limit mg/dl upper limit mg/dl (c) Based on your results in part (b), do you think this patient still has a calcium deficiency? Explain. O Yes. This confidence interval suggests that the patient may still have a calcium deficiency. Yes. This confidence interval suggests that the patient no longer has a calcium deficiency. O No. This confidence interval suggests that the patient may still have a calcium deficiency. O No. This confidence interval suggests that the patient no longer has a calcium deficiency.What percentage of hospitals provide at least some charity care? Based on a random sample of hospital reports from eastern states, the following information is obtained (units in percentage of hospitals providing at least some charity care): 56.9 55.9 53.3 65.7 59.0 64.7 70.1 64.7 53.5 78.2 I USE SALT Assume that the population ofx values has an approximately normal distribution. (a) Use a calculator with mean and sample standard deviation keys to nd the sample mean percentage )7 and the sample standard deviation 5. (Round your answers to four decimal places.) x: :0. (b) Find a 90% condence interval for the population average 9 of the percentage of hospitals providing at least some charity care. (Round your answers to one decimal place.) lower limit E % upper limit E %