Here, the maximum frequency is 25, and the class corresponding to this frequency is 40 - 50
So, the modal class is 40 – 50.
lower limit (l) of modal class = 40,
class size(h) = 10
frequency (f1) of the modal class = 25
frequency (f0) of class preceding the modal class = 12
frequency (f2) of class succeeding the modal class = 10
Now, let us substitute these values in the formula