# Frequency Distribution

Here we will discuss about the frequency distribution with examples.

(i) Unclassified Frequency Distribution:

 Marks Obtained4203039404549506570798090Total Number of Students377135192512450

In the above table we have an example of unclassified frequency distribution. It shows the number of students obtaining certain marks. For example, the table shows 4 marks were attained by 3 students, 20 marks were obtained by 7 students, etc. So the frequency of 4 marks is 3, the frequency of 20 marks is 7, etc.

(ii) Classified Frequency Distribution:

 Marks ObtainedFrom 0 to under 20From 20 to under 40From 40 to under 60From 60 to under 80From 80 to under 100 Number of Students315 (i.e., 7 + 7 + 1)18 (i.e., 3 + 5 + 1 + 9) 8 (i.e., 2 + 1)6 (i.e., 2 + 4)

Total number of students = 50

In the above table we have an example of classified frequency distribution. It shows the number of students obtaining marks between two numbers. For example, the table shows that 3 students obtained marks from 0 (included) to 20 (excluded), 15 students obtained marks from 20 (included) to 40 (excluded), etc. So the frequency of the class 0 to 20 (excluded) is 3, the frequency of the class 20 to 40 (excluded) in 15, etc.

The frequency of a class is the number of values of the variable appearing in the class.