6. An apartment complex developer is considering building apartments in College Town, but first wants to do a market study. A previous market study found a mean of $490.80 and standard deviation of $55. Suppose the apartment developer wants a 98% confidence interval estimate of the population mean with a margin of error of E = $10. What sample size is needed? 37 335 89 162

Beer Drinking. The mean annual consumption of beer per person in the US is 22.0 gallons . A random sample of 300 Washington D.C. residents yielded a mean annual beer consumption of 27.8 gallons. At the 10% significance level, do the data provide sufficient evidence to conclude that the mean annual consumption of beer per person for the nation’s capital differs from the national mean? Assume that the standard deviation of annual beer consumption for Washington D.C. residents is 55 gallons.

27. In a random sample of six mobile devices, the mean repair cost was $65.00 and the standard deviation was $14.00. Assume the population is normally distributed and use a t-distribution to find the margin of error and construct a 90% confidence interval for the population mean. Interpret the results.

5. In a random sample of five airlines, the round trip fare from Ontario to San Francisco is found to be $266, $288, $297, $316, and $384. Assume that airfares are normally distributed with a standard deviation of $45 dollars. a. find the sample mean. b. construct a 90% confidence interval for the population mean. c. construct a 95% confidence interval for the population mean. N(0,1)