Find the variance and standard deviation of the given set of data to the nearest tenth.
{440, 130, 280, 500, 150, 640, 760}
a) variance = 222.7, standard deviation = 49,595.9
b) variance = 49,595.9, standard deviation = 24,798
c) variance = 49,595.9, standard deviation = 222.7
d) variance = 57,861.9, standard deviation = 240.5

Part 1) variance = 49,595.9

Part 2) standard deviation = 222.7

Option C

Step-by-step explanation:

we have

set of data

step 1  

Find the mean  

Adds the values and divide by the number of values

In this problem the number of values is 7

step 2  

for each number: subtract the Mean and square the result  

step 3  

work out the mean of those squared differences  

----> this value is called the "Variance"  

step 4

The standard deviation is the square root of the variance

so

The standard deviation is equal to

walter needs to make at least 5 more cookies but no more than 40. 5 ≥ x ≥ 40;

step-by-step explanation:

walter has to make a minimum of 20 cookies. he already has 15 cookies made, so he must make 5 more to meet the minimum.

the maximum amount of cookies he can make is 55. he already has 15, so he has to make no more than 40 more cookies to meet the maximum.