Based on 100 customer satisfaction ratings, the Richardson marketing research firm would like you to confirm that the new virtual reality system receive a rating above 50. After data processing, you, the analyst, find that the sample mean is 50.99 and the sample standard deviation (s) is 3.360.

Show the Excel functions and results in Excel:

confidence level	alpha	alpha/2	t-alpha/2		degree of freedom (d.f.)=n-1
95%
99%
Find the critical values for t-based confidence intervals
t	t.inv

(a) Calculate the t-based 95% confidence interval for the sample mean.

(b) Calculate the t-based 99% confidence interval for the sample mean.

(c) Are you 95% confident that the mean customer satisfaction rating will be above 50? Why?

(d) Are you 99% confident that the mean customer satisfaction rating will be above 50? Why?

(e) Based on your answers to 2c and 2d above, how convinced are you that the customer satisfaction rating is above 50? Why?