The following sample was taken:
1, 9, 11, 3, 12, 15, 16, 8, 7, 8, 12, 3, 2, 6, 6, 7, 8, 10, 9, 5,
6, 7, 8, 6, 8, 7
a. Calculate the average
b. Estimate the variance
c. Build a 95% confidence interval for the standard
deviation.
Please, give your answer by hand. Thanks in
advance.