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 N 
  c. f 


Median= l  2  x h
 f 
 


where
= lower limit of the median class
h = width of the median class
f = frequency of the median class
c.f = cumulative frequency of class preceding the median class
N = the total frequency

Example-3:Find the median class and hence the median for the given distribution.
Marks 0-10 10-20 20-30 30-40 40-50 50-60
Number of Students 8 15 25 32 15 5
Solution:

Marks Number of students (f) Cumulative frequency
0-10 8 8
10-20 15 23

20-30 25 48
30-40 32 80
40-50 15 95

50-60 5 100
Total N = 100

Here, and cumulative frequency just greater than 50 is 80.
Now, the median class is 30 - 40.
 N 
  c. f 


Median= l  2  x h
 f 
 


where
= lower limit of the median class
h = width of the median class
f = frequency of the median class
c.f = cumulative frequency of class preceding the median class
N = the total frequency

Median = 30 + (50 - 48)

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