Draw a 'less than' ogive for the following distribution. Hence, find median
from the graph.
Answers
first you find commutative frequency
cf
2
10
22
32
48
56
59
60
then n= 60
n/2 = 30
form Mark's into less than type
median= 40
Given :
Frequency distribution of marks obtained by students of class
To Find :
To draw 'less than' ogive & using less than ogive we need to find median from 'Less than' ogive.
Solution:
Marks No. of Less Cumulative
students than frequency
0-10 02 10 02
10-20 08 20 10
20-30 12 30 22
30-40 10 40 32
40-50 16 50 48
50-60 08 60 56
60-70 03 70 59
70-80 01 80 60
Less than type ogive is drawn in attachment.
Median is given by the x-coordinate of the point corresponding to n/2 frequency of the ‘more than’ ogive or ‘less than’ ogive.
• In an ogive given data is plotted on X axis.
• Cumulative frequency is plotted on Y axis.
• So median is 45 marks (approx)
