Mode is the value which occurs most frequently in a set of observations and around which the other items of the set cluster densely. In other words, mode is the value of the variable which is predominant in the series. Thus in the case of discrete frequency distribution, mode is the value of x corresponding to maximum frequency.
In case of continuous frequency distribution, mode is given by the formula:
where l is the lower limit, h the magnitude and f1 the frequency of the modal class, fo and f2 are the frequencies of the classes preceding and succeeding the modal class respectively.