Calculate mean, median, mode, and range

1. Mean (The Average)
The mean is what most people think of as the "average."
*   How to find it:
    1.  Add up all the numbers in the data set.
    2.  Divide by the count of how many numbers there are.
*   Example: For the set {2, 2, 4, 8}
    *   Add: 2 + 2 + 4 + 8 = 16
    *   Divide: There are 4 numbers, so 16 ÷ 4 = 4.
    *   The mean is 4.

2. Median (The Middle)
The median is the middle number in an ordered data set.
*   How to find it:
    1.  Put the numbers in order from least to greatest.
    2.  Find the number exactly in the middle.
    *   If there are two middle numbers (in an even set), the median is the average of those two.
*   Example: For {2, 8, 4, 2} -> Order it first: {2, 2, 4, 8}
    *   The two middle numbers are 2 and 4.
    *   Find their average: (2 + 4) ÷ 2 = 3.
    *   The median is 3.

3. Mode (The Most Frequent)
The mode is the number that appears most often in a data set.
*   How to find it: Look for the number that repeats the most.
*   Example: For {2, 2, 4, 8}
    *   The number 2 appears twice, more than any other number.
    *   The mode is 2.
*   A data set can have one mode, more than one mode, or no mode at all.

4. Range (The Spread)
The range tells you how spread out the data is.
*   How to find it: Subtract the smallest number from the largest number.
*   Example: For {2, 2, 4, 8}
    *   Largest: 8
    *   Smallest: 2
    *   Subtract: 8 - 2 = 6.
    *   The range is 6.

Key Idea:
*   Mean: The "fair share" value.
*   Median: The "middle" value.
*   Mode: The "most popular" value.
*   Range: The "spread" of the values.