In mathematics, an average, or central tendency of a data set refers to a measure of the "middle" or "expected" value of the data set. There're many different descriptive statistics that can be chosen as a measurement of the central tendency of the data items. An average's a single value that's meant to typify a list of values. If all the numbers in the list are the same, then this number should be used. If the numbers aren't all the same, an easy way to get a representative value from a list's… (More on Average)