Exercise 3 Consider the data below that correspond to the monthly talk times (in minutes) of the mobile phones of 12 employees of one department (Customer Service) of a certain company (assume that talk times are normally distributed): 123 42 77 97 110 53 88 91 66 117 85 38 a) Estimate the mean monthly talk time of all employees in all departments of the company (i.e. calculate the best one-point estimate for the population mean). b) Estimate a 95% confidence interval for the mean monthly talk time of all employees of the company. c) Do you think that this sample of data is representative? Why or why not?

Exercise 3 Consider the data below that correspond to the monthly talk times (in minutes) of the mobile phones of 12 employees of one department (Customer Service) of a certain company (assume that talk times are normally distributed): 123 42 77 97 110 53 88 91 66 117 85 38 a) Estimate the mean monthly talk time of all employees in all departments of the company (i.e. calculate the best one-point estimate for the population mean). b) Estimate a 95% confidence interval for the mean monthly talk time of all employees of the company. c) Do you think that this sample of data is representative? Why or why not?