Median: How to calculate median of class intervals whose frequencies are given?

In Statistics Median is the method (process) to find the central tendency of Data 

What is Median?

By arranging the Numerical Datas in ascending or Descending order the Number that comes in the exact middle position is known as Median.

Steps to determine the Median 

Step -1

Numerical Data should be arranged in ascending or descending order.

Step -2

Then exact middle position of the Numerical Datas should be pointed out.

Process to find the exact middle position 

If the number of arranged numerical data 'n' is odd then exact middle position=(n+1)/2

If the number of arranged numerical data 'n' is even then exact middle position={(n/2)+(n/2)+1}÷2

STEP -3

The number in the exact middle position is the median.

Example 

Find the Median of 17,18,15,20,25,30,34

Solution: 

if we arrange the Numerical Datas in ascending order then the Datas are

15,17,18,20,25,30,34

Since the number of data is 7 which is an odd number so median=(7+1)/2 th number

                 =4th number=20

How to find median of frequency distribution table?

Find the median of the given frequency distribution table?

Data	Frequency
15	2
18	3
19	1
25	4
30	3

Solution:

Data	Frequency	Cumulative frequency
15	2	2
18	3	5
19	1	6
25	4	10
30	3	13

Here number of given data n=13

median position m=n / 2=13/2=6.5

since 6.5 is not present in the cumulative Frequency list then we have to take it's next higher number 10 from the cumulative Frequency list for Median position

There fore the median is 25

MEDIAN