Question

why Sigma is used in statistics to find mean

Answer 1

Dear student,

The symbol $\sum _{}^{}$ means "sum up".
Mean is defined as the average of a given data set.
Mean = $\frac{Sumofallobservations}{Totalno.ofobservations}$
As the numerator is the sum of all observations hence we use sigma as we are summing up all the observations given in the data set.
and in the denominator we are summing up the total no.of observations.
To denote the sum up we write sigma.

Regards