Final answer:
The range of the software coefficient of skewness is from -3 to +3, with negative values indicating left skewness and positive values indicating right skewness.
Step-by-step explanation:
The range of the software coefficient of skewness is typically between -3 and +3. This measure indicates the asymmetry of the probability distribution of a real-valued random variable about its mean. The negative values indicate data that are skewed left and the positive values indicate data that are skewed right. For example, if the mean value is greater than the median, as in the data set where the mean is 15.1, the median is 13.5, and the mode is 12, this indicates a right-skewed distribution. Similarly, when the mean is less than the median and the mode, it suggests a left-skewed distribution. The empirical rule, also known as the 68-95-99.7 rule, further provides insight into the data distribution in relation to standard deviations and z-scores, which doesn't directly provide skewness but is related to the spread of data around the mean.