Out of the seven digits total, the last four are variable. The value of each of these four digits can be from zero to nine, giving each of the four variable digits ten possible values. The total number of combinations possible within these four digits is calculated as 10 X 10 X 10 X 10, or 104, for a total number of possible combinations of 10,000.
Standard deviation = $21,200. Standard deviation is calculated as the square root of the variance; variance is calculated as follows, where M is the mean and N is the total number of scores.
Determine the coefficient of skewness using Pearson's method. 0.041. This is calculated as Sk = 3( - ) / Sx where denotes mean, denotes median, and Sx denotes the sample standard deviation. A value < 0 means the distribution is positively skewed.
Question 3, Part 2: The annual incomes of officers of another firm similar to TMV Industries were also studied. The mean was $129,000 and the standard deviation $8,612. Compare the means and dispersions in the two firms.
The mean income of officers in the two firms is almost identical. However, the dispersion as measured by the higher standard deviation of the second firm indicates that its officers' incomes have a greater variation than TMV's officers.