Your formula can be written differently if we take d1 F1 - F0 difference between modal class and previous class d2 F1 - F2 difference between modal class and next class Then d1 d2 F1 - F0 F1 - F2 2F1 - F0 - F1 so the formula is Z L1 d1d1 d2 i. By observing the given data set the number 23 occurs more number of times. H Size of the class interval assuming all class sizes to be equal f 1 Frequency of the modal class.
Now we have to simply calculate the mid value of the grouped data by dividing the sum of group data for the each sequence of the numbers.
Calculate the number of samples of a data set by summing up the frequencies. By observing the given data set the number 23 occurs more number of times. H Size of the class interval assuming all class sizes to be equal f 1 Frequency of the modal class. This formula gives a linear interpolation to estimate the actual value of the mode from grouped data.