Question

Find the standard deviation of the sample data set.

Answer 1

Answer:

the answer is B

Step-by-step explanation:

Answer 2

Answer:

Option A)  4.4 is the correct standard deviation of the the given data set.

Step-by-step explanation:

We are given the following data set:

127, 135, 128, 131, 133, 127, 122

Formula:

$\text{Standard Deviation} = \sqrt{\displaystyle\frac{\sum (x_i -\bar{x})^2}{n-1}}$

where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

$Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}$

Solving:

$Mean =\displaystyle\frac{903}{7} = 129$

Sum of squares of differences = 4 + 36 + 1 + 4 + 16 + 4 + 49 = 114

$S.D = \sqrt{\frac{114}{6}} = 4.358898944 \approx 4.4$

Option A) is the correct standard deviation of the the given data set.