Please do problems:
1, 2, 3, 4, 5, 38, 39, 40, 41, 42
8.1 A SINGLE POPULATION MEAN USING THE NORMAL DISTRIBUTION
Use the following information to answer the next five exercises: The standard deviation of the weights of elephants is known to be approximately 15 pounds. We wish to construct a 95% confidence interval for the mean weight of newborn elephant calves. Fifty newborn elephants are weighed. The sample mean is 244 pounds. The sample standard deviation is 11 pounds.
1.Identify the following:
- x¯x¯ = _____
- σ = _____
- n = _____
In words, define the random variables X and X¯¯¯X¯.
3.Which distribution should you use for this problem?
4.Construct a 95% confidence interval for the population mean weight of newborn elephants. State the confidence interval, sketch the graph, and calculate the error bound.
5.What will happen to the confidence interval obtained, if 500 newborn elephants are weighed instead of 50? Why?
8.2 A SINGLE POPULATION MEAN USING THE STUDENT T DISTRIBUTION
Use the following information to answer the next five exercises. A hospital is trying to cut down on emergency room wait times. It is interested in the amount of time patients must wait before being called back to be examined. An investigation committee randomly surveyed 70 patients. The sample mean was 1.5 hours with a sample standard deviation of 0.5 hours.
38.Identify the following:
- x¯x¯ =_______
- sxsx =_______
- n =_______
- n – 1 =_______
Define the random variables X and X¯¯¯X¯ in words.
40.Which distribution should you use for this problem?
41.Construct a 95% confidence interval for the population mean time spent waiting. State the confidence interval, sketch the graph, and calculate the error bound.
42.Explain in complete sentences what the confidence interval means.