ANSWER: Answer will include that the measures of variability provide a single number that tells how “spread out” scores are. When the scores are widely spread, this number gets larger. When they are close together, it gets smaller. The simplest way to indicate this “spread” is to use a measure called the range. The range is the difference between the highest and lowest scores in a group of scores. To obtain the standard deviation, one must first find the deviation (or difference) of each score from the mean and then square it. Then, these squared deviations are added and averaged (the total is divided by the number of deviations). Finally, by taking the square root of this average, one obtains the standard deviation.