Question

A distribution consists of three components with frequencies $300$,$200$ and $600$ having their means $16$,$8$ and $4$ respectively, then the mean of combined distribution is

Answer 1

Mean of combined distributions $=\sum \frac{f_i{x}_i}{f_i}=\frac{300\times 16+200\times 8+600\times 4}{300+200+600}=\frac{8800}{1100}=8$