Concept explainers
a.
Find the 99% confidence interval for the population proportion
b.
Find the 99% confidence interval for the population proportion
c.
Find the 99% confidence interval for the population proportion
d.
Find the 99% confidence interval for the population proportion
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An Introduction to Statistical Methods and Data Analysis
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- To check the quality of the run of a commercial laboratory, a duplicate analysis of a purified benzoic acid sample (68.8% C and 4.953 H) was requested. The relative standard deviation of the method is assumed to be s→ϭ= 4 ppt for carbon and 6 ppt for hydrogen. The results averaged 68.5% C and 4.882% H. At the 95% confidence level, is there any indication of systematic error in either analysis?arrow_forward) A study was conducted to determine if the salaries of librarians from two neighboring cities were equal. Asample of 15 librarians from each city was randomly selected. The mean from the first city was $28,900 with astandard deviation of $2300. The mean from the second city was $30,300 with a standard deviation of $2100.Construct a 95% confidence interval for µ1 - µ2.arrow_forwardSuppose a different police department says their SRS resulted in a 95% confidence interval of 10.1% to 15.1%. What is their point estimator and margin of error?arrow_forward
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