The difference between the greatest and least number.

To find range:

greatest-least

The number or numbers that shows up most in the set of data.

middle number

To find the median:

1. put numbers in order from least to greatest

  2. If odd amount of numbers median is easy to find, it's the middle number.

 3. If there is an even amount of numbers find the mean of the two middle numbers.

average

To find mean:

1. add up all numbers

      2. Divide by how many numbers there are