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8. [-/7.14 Points] DETAILS BBUNDERSTAT12 7.2.014.MI.S. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER How much does a sleeping bag cost? Let's say you want a sleeping bag that should keep you warm in temperatures from 20OF 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. 55 45 105 60 100 50 30 23 100 110 105 95 105 60 110 120 95 90 60 70 (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 = $ = $ (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 u of all summer sleeping bags. (Round your answers to two decimal places.) lower limit $ upper limit $ Need Help? Read It Master It 9. [-/7.14 Points] DETAILS BBUNDERSTAT12 7.2.016.S. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER 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 can stores are given below. Assume that the population of x values has an approximately normal distribution. 100 174 130 99 75 94 116 100 85 (a) Use a calculator with mean and sample standard deviation keys to find the sample mean startup cost x and sample standard deviation s. (Round your answers to four decimal places.) X = thousand dollars S : thousand dollars (b) Find a 90% confidence interval for the population average startup costs u for candy store franchises. (Ro your answers to one decimal place.) lower limit thousand dollars upper limit thousand dollars Need Help? Read It Watch It