Question

1.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 129 responses. The average time these 129 general managers had spent with their current company was 13.17 years. (Take it as known that the standard deviation of time with the company for all general managers is 3.2 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:

b) Find the margin of error for an 99% confidence interval to estimate the mean time a general manager had spent with their current company:

2.A random sample of ? measurements was selected from a population with standard deviation ?=16.4 and unknown mean ?. Calculate a 99 % confidence interval for ? for each of the following situations:

(a) ?=35, x bar =90.6 blank≤ μ ≤ blank

b)?=60, x bar =90.6 blank≤ μ ≤ blank

c)?=70, x bar =90.6 blank≤ μ ≤ blank

Answer 1