With 'random sampling' every item in the population has an equal probability of being selected.
In addition to mean and sample size you will need the individual scores.
The formula for standard deviation is:
S^2 = E(X-M)^2/N-1
Here's an example:
Data set: 4,4,3,1
Mean: 3
Sample size: 4
First, put the individual scores one after the other and subtract the mean from it.
4 - 3 = 1
4 - 3 = 1
3 - 3 = 0
1 - 3 = -2
Second, square the answers you got from step 1.
1^2 = 1
1^2 = 1
0^2 = 0
-2^2 = 4
Third, plug the values from step 2 into the formula.
S^2 = (1+1+0+4)/(4-1) = 6/3 = 2
Standard deviation = 2
From the given diagram, the following statements are true:
AB = BC
3y = 5y - 22
3y - 5y = -22
-2y = -22
y = 11
Similarly, m<DBE = 50 degrees
m<BED = 90 - m<DBE
m<BED = 90 - 50
m<BED = 40 degrees
Since BE = BC = 3y
BE = BC = 3(11) = 33
Also, 7x - 2 = 40
7x = 40 + 2
7x = 42
x = 6
Get the measure of m<BEA
m<BEA = 7x - 2
m<BEA = 7(6) - 2
m<BEA = 40 degrees
Learn more on angles here: brainly.com/question/16281260
Answer:
Step-by-step explanation:
3x - 18 = 8x - 9x - 21
3x - 18 = -x - 21
4x - 18 = -21
4x = -3
x = -3/4
answer is A
In the given question, the options are related to linear pair .
And according to linear pair, if a line cuts another line at a point, then the sum of the adjacent angles formed at that point is 180 degree.
Therefore, from the given diagram we can say that, angles WXY and YXZ are linear pair, so there sum have to be 180.

And the correct option is the third option .