Question

A contractor records the areas, in square feet, of several houses in a neighborhood to determine data about the neighborhood. Which formula should be used to calculate the standard deviation?

Answer 1

The answer is B on edge

Explanation:

The second answer is A: The data is a sample and is expected to be more dispersed from the mean.

Answer 2

Explanation:

Given that a contractor records the areas, in square feet, of several houses in a neighborhood to determine data about the neighborhood.

Let X1, X2,...Xn be the data set

We find mean of this by the formula sum/n

Mean =
`\bar x =(x_1+x_2+x_3+..+x_n)/(n)`

Now variance is calculated as sum of squares of deviations of each entry from this mean.

Var(x) =
`(1)/(n)  \Sigma _(i=1) ^n(x_i-\bar x)^2`

Standard deviation = square root of variance

Thus first mean, then variance then sd deviation is calculated.