A simple random sample of 285 part-time workers finds that the average wage is $19.43 with a standard deviation of $2.61.

A simple random sample of 285 part-time workers finds that the average wage is $19.43 with a standard deviation of $2.61. The data follows the normal curve. (Make sure to also state your results in a sentence.)

a. Identify the population, sample, parameter, and statistic.

b. Find an 80% confidence interval for the average wage of part-time workers.

c. As part of an effort to push for higher wages, suppose that labor unions want to know, with 99% confidence, the average wage of part-time workers to within $0.25. Determine the appropriate sample

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orchestra answered 1 year ago

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