Using it's concept, the standard deviation for the given data-set is of 8.22.
<h3>What are the mean and the standard deviation of a data-set?</h3>
- The mean of a data-set is given by the <u>sum of all values in the data-set, divided by the number of values</u>.
- The standard deviation of a data-set is given by the square root of the <u>sum of the differences squared between each observation and the mean, divided by the number of values</u>.
The mean for this problem is:
M = (17 + 26 + 28 + 9 + 30 + 29 + 6 + 21 + 23)/9 = 21
Hence the standard deviation is:

More can be learned about the standard deviation of a data-set at brainly.com/question/12180602
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Area is 28 for number 33.
7*8=56
56/2=28
Answer:
Last Option
Step-by-step explanation:
We have a triangle and we know its three sides.
We want to find one of your anguos. Then we use the cosine theorem.

Where

Now we solve for x from the equation

Mathematically written:
3 * x + 7 = 25
3x + 7 = 25
3x = 25 - 7
3x = 18
x = 18 / 3
x = 6
Proof:
3 * 6 + 7 = 25
18 + 7 = 25
25 = 25 → both sides of the equation are equal, our answer is correct
Notes:
A number - Is an unknown number, called a variable, which in this case is substituted by the letter x.
Hope it helped,
BioTeacher101
Answer:
C=45
if 9/11 = c/55 you have to divide the c/55 by 9/11, resulting in c/9 = 5
multiply 9 by 5 to get 45
Step-by-step explanation: