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

Answer:

Step-by-step 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 = $\bar x =\frac{x_1+x_2+x_3+..+x_n}{n}$

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

Var(x) = $\frac{1}{n} \Sigma _{i=1} ^n(x_i-\bar x)^2$

Standard deviation = square root of variance

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

Answer 2

Answer:

The answer is B on edge

Step-by-step explanation:

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