Question

The number of cars sold at a dealership over several weeks is given below. 14, 23, 31, 29, 33 What is the standard deviation for this set of population data?

Answer 1

The answer is A.6.9.............................

Answer 2

Answer:

Hence, standard deviation is: 6.87

Step-by-step explanation:

We are given the data as:

14    23    31    29   33

The mean of the data is calculated as the ratio of the sum of all the data points divided by the total number of data points.

Hence,

$Mean(M)=\dfrac{14+23+31+29+33}{5}\\\\Mean(M)=\dfrac{130}{5}\\\\Mean(M)=26$

Now we find the difference between mean and each data entry.

14-26     23-26      31-26      29-26       33-26

-12        -3         5         3          7

Now squaring these numbers to get:

144      9        25         9         49

Now, finding the mean we get the variance(V) as:

$V=\dfrac{144+9+25+9+49}{5}\\\\\\V=\dfrac{236}{5}\\\\\\V=47.2$

Now, standard deviation is defined as the square root of the variance.

Hence standard deviation is:

$\sqrt{47.2}=6.87$

Hence, standard deviation is: 6.87