(Answers are given but could you please work through the problemand show me the steps?)
Chapter 8
A local health center noted that in a sample of 400 patients, 80were referred to them by the local hospital.
a. | Provide a 95% confidence interval for all the patients who arereferred to the health center by the hospital. |
b. | What sample size would be required to estimate the proportion ofall hospital referrals to the health center with a margin of errorof .04 or less at 95% confidence? |
A simple random sample of 36 items resulted in a sample mean of40 and a standard deviation of 12. Construct a 95% confidenceinterval for the population mean.
Six hundred consumers belonging to the 25-34 age group wererandomly selected in a city and were asked whether they would liketo purchase a domestic or a foreign automobile. Their responses aregiven below.
Preference | Frequency |
Domestic | 240 |
Foreign | 360 |
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Develop a 95% confidence interval for the proportion of all suchconsumers who prefer to purchase domestic automobiles.
