Chapter 9 Exercise 1212. The American Sugar Producers Association wants to estimate the mean yearly sugar consumption. A sample of 16 people reveals the mean yearly consumption to be 60 pounds with a standard deviation of 20 pounds.
A. What is the value of the population mean? What is the best estimate of this value?Answer: The population mean is unknown because the sum of the values is not known. The best estimate is 60 pounds, which is also the sample mean.
The population mean is the sum of all the values in the population divided by the number of values in the population.
B. Explain why we need to use the t distribution. What assumption do you need to make?Answer: We need to use the t distribution because the standard deviation is unknown and the sample size is less than 30. I would need to make a normality assumption.
C. For a 90 percent confidence interval, what is the value of t?Answer: N-1 = 15, which gives a value of df of 15. Using the 90% interval t is equal to: 1.753D. Develop the 90 percent confidence interval for the population mean.
Answer:X ÃÂ± t S which equals: 68.765 and 51.235Ã¢ÂÂnX = 60, t = 1.753, S = 20, n = 16.
The endpoints for the confidence interval are: 68.765 for the upper confidence limit and 51.235 for the lower confidence limit.
E. Would it be reasonable to conclude that the population mean is 63 pounds?Answer: Yes it would be reasonable to conclude that the population mean is 63 pounds because it falls between the 68.765 and 51.235 intervals.
Chapter 10 Exercise 6For Exercises 5-8: (a) State the null hypothesis and the alternate hypothesis. (b) State the decision rule. (c) Compute the value of the test statistic. (d) What...