# A survey was conducted by a group of students as a part of their environment awareness programme, in which they collected the following data regarding the number of plants in 20 houses in a locality. Find the mean number of plants per house.

## Question :

Which method do you use for finding the mean and why ?

## Solution :

Mean = $$\sum f_ix_i\over \sum f_i$$ = $$162\over 20$$ = 8.1

Here, we have used direct method because numerical values of $$x_i$$ and $$f_i$$ are small.