1. A student was asked to evaluate the mean and standard deviation for following sample of n = 5

81, 87, 89, 86, & 87. To simplify arithmetic, the student first subtracted 80 points from each score to obtain the new sample consisting of 1, 7, 9, 6, & 7. The mean and standard deviation for new sample were then evaluated to be M = 6 and s = 3. What are the values of mean M and the standard deviation s for original sample? Hint:What takes place to the mean when you subtract the constant from each observation?

2.  There're two different formulas or methods which can be employed to compute SS.

1. Under what circumstance is the definitional formula easy to use? Hint: Refer to the text
2. Under what circumstance is the computational formula easy to use? Hint: Refer to the text