This number is a measure of central tendency . Remember the mode is a peak in the distribution. Notice how the mean is affected by the extremes. In this example the median is 79 or halfway between 75 and 83. The range of scores is from 14 to 100 or 86, i.e., the difference between the lowest and the highest.
Range is one measure of variability.
Range was discussed above and is a crude measure of variability. The standard measure of spread or variability is the standard deviation. A large variance reflects a wide spread in the data. Standard deviation measures the spread of from the mean. Roughly speaking, it is the average distance of the data from the mean.