42 lines
1.3 KiB
Markdown
42 lines
1.3 KiB
Markdown
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---
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title: Mean
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---
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## Mean
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The most common measure of central tendency, or a value used to describe a set of numbers, is the arithmetic average, or mean.
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To find the mean (*A*) of a set of numbers , you add their values and divide by the number of values (*n*).
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<br>
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### Examples
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* **1, 4, 5, 2, 3**
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(1 + 4 + 5 + 2 +3) / 5 = 3
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* **20, 14, 23**
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(20 + 14 + 23) / 3 = 19
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* **-12, -20, -16, -21**
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(-12, -20, -16, -21) / 4 = -17.25\
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<br>
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The mean can be a great way to describe a set of numbers. However, it is important to realize that one value that is much higher or lower than the other values, refered to as an outlier, in the set can cause the mean to inaccurately represent the set of numbers. For instace, if you have a set of numbers primarily composed of small numbers that contains one large number, the average will end up being larger than a majority of the numbers, inaccurately portraying the set of numbers as being higher than they actually are.
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### Examples
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* **2, 7, -3, 1, 0, 2, 857**
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(2 + 7 + (-3) + 1 + 0 + 2 + 857) / 7 = 123.71
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* **1276, 1141, 1271, 1053, 1**
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(1276 + 1141 + 1271 + 1053 + 1) / 5 = 948.4
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#### More Information:
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* 
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