Answer:
CI = {9.947; 12.253}
Step-by-step explanation:
Average time (μ) = 11.1 years
Standard deviation (σ) = 4.5 years
Sample size (n) = 101 responses
Z-score for a 99% confidence interval (z) = 2.576
The confidence interval is defined by the following expression:
[tex]\mu \pm z*\frac{\sigma}{\sqrt{n}}[/tex]
The lower (L) and upper (U) limits of the 99% confidence interval is:
[tex]L= 11.1 - 2.576*\frac{4.5}{\sqrt{101}} \\L=9.947\\U= 11.1+ 2.576*\frac{4.5}{\sqrt{101}} \\U=12.253\\[/tex]
The 99% confidence interval for the mean number of years general managers of major-chain hotels have spent with their current company is CI = {9.947; 12.253}