Question

Basic Computation: Class Limits A data set with whole numbers has a low value of 10 and a high value of 120. Find the class width and class limits for a frequency table with 5 classes.

 

Answer 1

Given :

Value of largest observation = 120

value of smallest observation = 10

and required number of classes = 5

Class width = ( 120-10) /5 = 22

Hence the class width of each classes is 22.

There are two types of classification inclusive type of classification and exclusive type classifiaction.

a) Inclusive type of classification : Both the limit are considered.

i.e. if the class is 10-32 and values of observation are 10 and 32, both the values are considered in the same class.

Since minimum value is 10 and maximum value is 120

Class	Lower Limit	Upper limit
10-32	10	32
33-55	33	55
56-78	56	78
79-101	79	101
102-124	102	124

b) Exclusive type classification ( Continuous type classification) : One of the limit are excluded. Generally upper limit of class is excluded, it will be considered in next class.For last class upper limit is considered in the same class.

i.e. If the class is 10-32 and value of the observations are 10 and 32, 10 is considered in 10-32 classs and 32 will be considered in next class.

Class	Lower Limit	Upper limit
10-32	10	32
32-54	32	54
54-76	54	76
76-98	76	98
98-120	98	120