Question

NOTE For each question Note if Sigma is known or unknown and post the z or t value for that problem with your answer. Problem 1: A random sample of 80 group leaders, supervisors, and similar personnel at General Motors revealed that, on average, they spent 6.0 years in a particular job before being promoted. The standard deviation using historical data was 1.5 years. Construct a 95% confidence interval.

          NOTE
For each question Note if Sigma is known or unknown and post
the z or t value for that problem with your answer.
Problem 1: A random sample of 80 group leaders, supervisors, and similar personnel at
General Motors revealed that, on average, they spent 6.0 years in a particular job before
being promoted. The standard deviation using historical data was 1.5 years. Construct a 95%
confidence interval.

NOTE
For each question Note if Sigma is known or unknown and post
the z or t value for that problem with your answer.
Problem 1: A random sample of 80 group leaders, supervisors, and similar personnel at
General Motors revealed that, on average, they spent 6.0 years in a particular job before
being promoted. The standard deviation using historical data was 1.5 years. Construct a 95%
confidence interval.

Added by Timothy H.

Elementary Statistics a Step by Step Approach

Allan G. Bluman 9th Edition

Instant Answer

Solved by Expert Cheng Zhang

06/12/2022

Step 1

5 years) and the sample size is large (n = 80), we will use the z-score for a 95% confidence interval, which is 1.96. Show more…

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NOTE For each question Note if Sigma is known or unknown and post the z or t value for that problem with your answer. Problem 1: A random sample of 80 group leaders, supervisors, and similar personnel at General Motors revealed that, on average, they spent 6.0 years in a particular job before being promoted. The standard deviation using historical data was 1.5 years. Construct a 95% confidence interval. NOTE For each question Note if Sigma is known or unknown and post the z or t value for that problem with your answer. Problem 1: A random sample of 80 group leaders, supervisors, and similar personnel at General Motors revealed that, on average, they spent 6.0 years in a particular job before being promoted. The standard deviation using historical data was 1.5 years.Construct a 95% confidence interval.