A personnel manager has found that historically the scores on aptitude tests given two applicants for...

A personnel manager has found that historically the scores on aptitude tests given two applicants for entry level positions follow a normal distribution. A random sample of 19 test scores from the current group of applicants has a sample mean score of 187.9 points and a sample standard deviation as 32.4 points.

a. find the margin of error.

b. construct a confidence interval estimate for the population mean with 80% level of confidence.

c. construct a confidence interval estimate for population mean with 85% level of confidence.

Expert Solution

orchestra answered 1 year ago

A personnel manager has found that historically the scores on aptitude test given to applicants for...

A personnel manager has found that historically the scores on aptitude test given to applicants for entry level positions follow a normal distribution. A random sample of nineteen test scores from the current group of applicants had a sample mean score of 187.9 points and sample standard deviation as 32.4 points. a. Find the margin of error. b. Construct a confidence interval estimate for population mean with 80 percent level of confidence. c. Construct a confidence interval estimate for population...

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