Mean of Grouped Data (Without Class-Interval)

If the data is organized in such a way that there is no class interval then we can calculate the mean by

\bar x=\dfrac{f_1x_1+f_2x_2+....+f_nx_n}{f_1+f_2+....+f_n}

=\dfrac{\sum\limits^n_{i=1}f_ix_i}{\sum\limits^n_{i=1}f_i}

where, x_1,x_2,x_3,....x_n are the observations

f_1,f_2,f_3,.....f_n are the respective frequencies of the given observations.

Grouped Population Mean
xffx
2040800
40602400
60301800
80504000
100202000
 200 \sumfx = 11000 

Here, x_1,x_2,x_3,x_4,x_5 are 20, 40, 60, 80, 100 respectively and  f_1,f_2,f_3,f_4,f_5 are 40, 60, 30, 50, 20 respectively.

\bar x=\dfrac{f_1x_1+f_2x_2+.....+f_nx_n}{f_1+f_2+....+f_n}

\bar x=\dfrac{11000}{200}=55

Scroll to Top