Question: The manager of a pizza chain in Albuquerque New Mexico
The manager of a pizza chain in Albuquerque, New Mexico, wants to determine the average size of their advertised 16-inch pizzas. She takes a random sample of 25 pizzas and records their mean and standard deviation as 16.10 inches and 1.8 inches, respectively. She subsequently computes the 95% confidence interval of the mean size of all pizzas as [15.36, 16.84]. However, she kinds this interval to be too broad to implement quality control and decides to re-estimate the mean based on a bigger sample. Using the standard deviation estimate of 1.8 from her earlier analysis, how large a sample must she take if she wants the margin of error to be under 0.5 inch?
Answer to relevant QuestionsMortgage lenders often use FICO ® scores to check the credit worthiness of consumers applying for real estate loans. In general, FICO scores range from 300 to 850 with higher scores representing a better credit pro. A ...An economist would like to estimate the 95% confidence interval for the average real estate taxes collected by a small town in California, ravaged by the economic crisis. In a prior analysis, the standard deviation of real ...Explain why the following hypotheses are not constructed correctly.a. H0: ≤ 10; HA: ≥ 10b. H0: ≠ 500; HA: µ = 500c. H0 : p ≤ 0.40; HA: p > 0.42d. H0 : ≤ 128; HA: > 128The manager of a large manufacturing firm is considering switching to new and expensive software that promises to significantly reduce its assembly costs. Before purchasing the software, the manager wants to conduct a ...Customers at Costco spend an average of $130 per trip (The Wall Street Journal, October 6, 2010). One of Costco’s rivals would like to determine whether its customers spend more per trip. A survey of the receipts of 25 ...
Post your question