Question

Find the mode of the given data:

Class Interval	0 – 20	20 – 40	40 – 60	60 – 80
Frequency	15	6	18	10

Answer 1

Here the maximum class frequency is 18, and the class corresponding to this frequency is 40-60. 

So, the modal class is 40 - 60. 

Now, Modal class = 40 - 60, lower limit (/) of modal class – 40, class size (h) = 20, 

Frequency (f₁) of the modal class =18, 

Frequency (f₀) of class preceding the modal class = 6, 

Frequency (f₂) of class succeeding the modal class = 10. 

Now, let us substitute these values in the formula:

= 40 + 12 

= 52 

Hence, the mode is 52.