The Range
The Range is simply the difference between the highest value and the lowest value. A large range implies a great deal of dispersion, but since it is dependent only upon the maximum and minimum scores, the sample's true dispersion is unknown.
What is the range of our sphere population? That is easy enough to calculate.
Range = 13-1
= 12
A more precise way of calculating the spread of values within a population is the Variance and Standard Deviation.
1:9