Answer:
First choice
Step-by-step explanation:
The difference quotient in general is
. To get an expression for
, replace x with x + h.
For this question,

Factor
out of the numerator.

Answer:
The sample standard deviation is 393.99
Step-by-step explanation:
The standard deviation of a sample can be calculated using the following formula:
![s=\sqrt[ ]{\frac{1}{N-1} \sum_{i=1}^{N}(x_{i}-{\displaystyle \textstyle {\bar {x}}}) ^{2} }](https://tex.z-dn.net/?f=s%3D%5Csqrt%5B%20%5D%7B%5Cfrac%7B1%7D%7BN-1%7D%20%5Csum_%7Bi%3D1%7D%5E%7BN%7D%28x_%7Bi%7D-%7B%5Cdisplaystyle%20%5Ctextstyle%20%7B%5Cbar%20%7Bx%7D%7D%7D%29%20%5E%7B2%7D%20%7D)
Where:
Sample standart deviation
Number of observations in the sample
Mean value of the sample
and
simbolizes the addition of the square of the difference between each observation and the mean value of the sample.
Let's start calculating the mean value:




Now, let's calculate the summation:


So, now we can calculate the standart deviation:
![s=\sqrt[ ]{\frac{1}{N-1} \sum_{i=1}^{N}(x_{i}-{\displaystyle \textstyle {\bar {x}}}) ^{2} }](https://tex.z-dn.net/?f=s%3D%5Csqrt%5B%20%5D%7B%5Cfrac%7B1%7D%7BN-1%7D%20%5Csum_%7Bi%3D1%7D%5E%7BN%7D%28x_%7Bi%7D-%7B%5Cdisplaystyle%20%5Ctextstyle%20%7B%5Cbar%20%7Bx%7D%7D%7D%29%20%5E%7B2%7D%20%7D)
![s=\sqrt[ ]{\frac{1}{15-1}*(2173160)}](https://tex.z-dn.net/?f=s%3D%5Csqrt%5B%20%5D%7B%5Cfrac%7B1%7D%7B15-1%7D%2A%282173160%29%7D)
![s=\sqrt[ ]{\frac{2173160}{14}}](https://tex.z-dn.net/?f=s%3D%5Csqrt%5B%20%5D%7B%5Cfrac%7B2173160%7D%7B14%7D%7D)

The sample standard deviation is 393.99
4/5 is the the fraction of a pound is eighty pence