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## Mean Of A Dataset

#### Introduction

The mean of a set of numbers is also known as the average value in the data set. Also known as the arithmetic mean, it is defined as the sum of all the values in the data set divided by the number of values in the set.

#### Terms

Mean - The mean is defined as the sum of all values divided by the number of values. Also known as Average

## Lesson

To find the mean of a set of numbers, simply add up all the values and divide by the number of values. For a set of n numbers , the formula for the mean is

For example, the average of the set of numbers is

## Examples

#### Find The Mean (Example #1)

Find the mean
To find the mean, first add all the numbers together:
There are five numbers in the list so we divide by five:
The mean of the set is 3

#### Find The Mean (Example #2)

Avery went to the store every day. On Monday he spent 31 minutes, on Tuesday 27 minutes, on Wednesday 27 minutes, on Thursday 42 minutes, on Friday 29 minutes, and on Saturday 60 minutes. What was the average time that Avery spent at the store?
To find the mean, first add all the numbers together:
There are six numbers in the list so we divide by six:
The mean of the set is 36

#### Find The Mean (Example #3)

Find the mean
To find the mean, first add all the numbers together:
There are six numbers in the list so we divide by six:
The mean of the set is 6.33

#### Find The Mean (Example #4)

Find the mean
To find the mean, first add all the numbers together:
There are six numbers in the list so we divide by six:
The mean of the set is 6.4