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A study of the career paths of hotel general managers sent questionnaires to an

ID: 3133347 • Letter: A

Question

A study of the career paths of hotel general managers sent questionnaires to an SRS of 230 hotels belonging to major U.S. hotel chains. There were 119 responses. The average time these 119 general managers had spent with their current company was 11.63 years. (Take it as known that the standard deviation of time with the company for all general managers is 1.3 years.)

A.Find the margin of error for an 80% confidence interval to estimate the mean time a general manager had spent with their current company:_____ years

B.Find the margin of error for a 99% confidence interval to estimate the mean time a general manager had spent with their current company:_____ Years

Explanation / Answer

A study of the career paths of hotel general managers sent questionnaires to an SRS of 230 hotels belonging to major U.S. hotel chains. There were 119 responses. The average time these 119 general managers had spent with their current company was 11.63 years. (Take it as known that the standard deviation of time with the company for all general managers is 1.3 years.)

A.Find the margin of error for an 80% confidence interval to estimate the mean time a general manager had spent with their current company: 0.1527 years

margin of error when known, z* /sqrt(n)

Z value for 80% level, z=1.282

margin of error=1.282*1.3/sqrt(119)

= 0.1527

B.Find the margin of error for a 99% confidence interval to estimate the mean time a general manager had spent with their current company: 0.3070 Years

Z value for 99% level, z=2.576

margin of error=2.576*1.3/sqrt(119)

= 0.3070