How is standard deviation calculated?

Standard deviation is a measure of the amount of variation or dispersion in a set of values. To calculate it, you first determine the mean (average) of the data set. Next, for each data point, you subtract the mean and then square the result. This gives you the squared deviations. After calculating all the squared deviations, you take the average of these values. Finally, the standard deviation is the square root of this average of squared deviations.

This process captures how spread out the values in the dataset are around the mean, providing insight into the overall distribution. The square root is taken to bring the measure back to the same unit as the original data since squaring the deviations will result in larger values that could misrepresent the variability when interpreted in context. Thus, option B accurately describes the correct method for calculating standard deviation.