Compute the mode of the following data:


Class



0 - 20



20 - 40



40 - 60



60 - 80



80 - 100



Frequency



25



16



28



20



5


Here, the maximum class frequency is 28.

The class corresponding to this frequency is the modal class. ⇒ modal class = 40 - 60


∴ lower limit of the modal class (l) = 40


Modal class size (h) = 20


Frequency of the modal class (f1) = 28


Frequency of class preceding the modal class (f0) = 16


Frequency of class succeeding the modal (f2) = 20


Mode is given by,



⇒


⇒


⇒ Mode = 40 + 12 = 56


Hence, the mode is 56.


2