Mean, median, and mode are measures of central tendency. That just means they help describe the center or typical value of a set of numbers (called a data set).
Each one finds the “center” in a different way.
1. Mean
The mean is what we usually call the average.
How to Find the Mean
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Add all the numbers
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Divide by how many numbers there are
Formula
Mean={Sum of all values} / {Number of values}
Example
Data set: 2, 4, 6, 8
{2 + 4 + 6 + 8}/{4} = {20}/{4} = 5
👉 Mean = 5
2. Median
The median is the middle number when the data is listed in order from least to greatest.
Steps to Find the Median
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Put the numbers in order
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Find the middle value
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If there is one middle number, that’s the median
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If there are two middle numbers, average them
Example (Odd Number of Values)
Data set: 3, 5, 7
Median = 5
Example (Even Number of Values)
Data set: 2, 4, 6, 8
Middle numbers: 4 and 6
{4 + 6}/{2} = 5
👉 Median = 5
3. Mode
The mode is the number that appears most often in the data set.
Important Notes
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A data set can have one mode, more than one mode, or no mode
Examples
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1, 2, 2, 3 → Mode = 2
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4, 4, 6, 6 → Modes = 4 and 6
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1, 2, 3 → No mode
Comparing Mean, Median, and Mode
| Measure | What It Finds |
|---|---|
| Mean | Average |
| Median | Middle value |
| Mode | Most frequent value |
Why Are They Important?
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Used in statistics and data analysis
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Help summarize large sets of data
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Used in school grades, sports stats, surveys, and science