Question

2/4 POINTS PREVIOUS ANSWERS BBUNDERSTAT12 7.2.016. MY NOTES ASK YOUR TEACHER 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 and sample standard deviations. (Round your answers to one decimal place.) 96 180128907594116 100 es (a) Use a calculator with mean and sample standard deviation keys to find the sample mean sartup cost thousand dollars thousand dollars for candy store franchises (Round your answers to one decimal place) (b) Find a 90% confidence interval for the population average startup costs thousand dollars er limit 1242 x thousand dollars Need Help?

Answer 1

• 90 % confidence for the population mean μ is upper limit 87.5
• 90 % confidence for the population mean μ is lower limit 126.7
  Solution: The provided sample mean is X = 107.1 and the sample standard deviation is s = 31.6. The size of the sample is n = 9 and the required confidence level is 90%. The number of degrees of freedom are df = 9-1= 8, and the significance level is a = 0.1. Based on the provided information, the critical t-value for a = 0.1 and df = 8 degrees of freedom is te = 1.86. The 90% confidence for the population mean u is computed using the following expression ly_tc X Site XS C1=(* - 8 + termine) vn vn Therefore, based on the information provided, the 90 % confidence for the population mean u is 1.86 x 31.6 044 1.86 x 31.6 C1 = (107.1 – 1.86 X32.0, 107.1 + 1.36x31.6) 19 19 = (107.1 – 19.587, 107.1 + 19.587) = (87.513, 126.687)