# Quadstat Output - Arithmetic Mean

Submitted by Anonymous (not verified) on May 15, 2019 - 12:29 PM

## Computing the Average

To compute the average, $\bar{x}$, we must sum all the observations in the column X.npreg. and then divide by the number of observations.

First, let us list the observations in column X.npreg.. The first ten observations include:
6, 1, 1, 3, 2, 5, 0, 1, 3, 9.

We have a total of 332 observation(s). So, $n =332.$

Now, $\bar{x} = \frac{\sum\limits_{i=1}^n x_i}{n}.$

$\sum\limits_{i=1}^n x_i = \sum\limits_{x=1}^{332}x_i = 6 + 1 + \cdots + 1 = 1157.$

Therefore, $\bar{x} = \frac{\sum\limits_{i=1}^n x_i}{n} = \frac{6+1+ \cdots + 1}{332}=3.48.$

So, $\bar{x} =3.48$.