CHAPTER 6 Section 6-1 6-1. 6-3. 6-5. 6-7. No, usually not. For example if the sample is {2, 3} the mean is 2.5 which is not an observation in the sample. No, usually not. For example, the mean of {1, 4, 4} is 3 which is not even an observation in the sample. Yes. For example, {5, 5, 5, 5, 5, 5, 5}, the sample mean = 5, sample standard deviation = 0 Sample average: x = x i i=1 n n = 592.035 = 74.0044 mm 8 Sample variance: x i = 592.035 i=1 8 8 x i 2 = 43813.18 031 i=1 n 2 x n i=1 i 2 x i - ( 592.035 ) 43813.18031- 2