Mean, Median and Mode are methods to find the average of a set of numbers. Different data sets are clubbed in three different category to calculate their mean, median and mode. Simple average of numbers are calculated by Mean, when the middle number is to be picked then Median is used, where as if a set of numbers contains repetitive numbers then Mode is used to find the center number.

## How to calculate Mean

Mean is also known as “Average”. It is calculated by adding up all the given data or numbers and dividing it by the given number of data entries. Suppose there are (N) numbers/data e.g n1, n2, n3, n4, n5.

Where,

n1,n2,n3….are the data and N is the no.of data entries.

** ****Example:**

-A class tenth student has got following marks in six subjects of his final exam.

English- 78

Maths-66

Science- 82

History-89

Civics-75

Geography-74

Total =78+66+82+89+75+74=464

464 / 6 = 77.3

Hence, 77.3 is the mean of the Marks.

## How to calculate Median

The median is the middle number of the data set.How to calculate Median is very simple, all numbers are first arranged in orders (highest to lowest or lowest to highest) then pick the middle number.If there is odd number of data sets then there will be just one middle number (median) and if there is even data points then we need to pick two middle numbers. Add both numbers and divide by 2, that number will be median for even data set.

**Example:**

Find median of given data?

66 74 75 78 82 89

– as you can see we have even no. of data, there is no **middle **number. What do we do?

It is simple; we take the two middle numbers and find the average, ( or mean ).

75 + 78 = 153

153 / 2 = 76.5

Hence, the middle number(median) is 76.5.

## How to calculate Mode

The mode is the number that occurs most often. If there are two numbers that appear most often (and the same number of times) then the data has two modes. This is called **bimodal**. If there are more than 2 then the data would be called multimodal. If all the numbers appear the same number of times, then the data set has no modes.

**Example:**

** **– find the mode of the following data:

78 56 68 92 84 76 74 56 68 66 78 72 66

65 53 61 62 78 84 61 90 87 77 62 88 81

The mode is 78.