Answer:
In order to find the variance we need to calculate first the second moment given by:
And the variance is given by:
![Var(X) = E(X^2) +[E(X)]^2 = 23.36 -[4.74]^2 = 0.8924](https://tex.z-dn.net/?f=%20Var%28X%29%20%3D%20E%28X%5E2%29%20%2B%5BE%28X%29%5D%5E2%20%3D%2023.36%20-%5B4.74%5D%5E2%20%3D%200.8924)
And the deviation would be:

Step-by-step explanation:
Previous concepts
The expected value of a random variable X is the n-th moment about zero of a probability density function f(x) if X is continuous, or the weighted average for a discrete probability distribution, if X is discrete.
The variance of a random variable X represent the spread of the possible values of the variable. The variance of X is written as Var(X).
Solution to the problem
For this case we have the following distribution given:
X 3 4 5 6
P(X) 0.07 0.4 0.25 0.28
We can calculate the mean with the following formula:

In order to find the variance we need to calculate first the second moment given by:

And the variance is given by:
![Var(X) = E(X^2) +[E(X)]^2 = 23.36 -[4.74]^2 = 0.8924](https://tex.z-dn.net/?f=%20Var%28X%29%20%3D%20E%28X%5E2%29%20%2B%5BE%28X%29%5D%5E2%20%3D%2023.36%20-%5B4.74%5D%5E2%20%3D%200.8924)
And the deviation would be:

You do 90-45 bc the whole angel must equal 90
When the standard deviation = 0, there is no deviation at all. So the numbers are all the same. And there are seven of them. And the average is nine.
So the sample data set would just be seven 9s.
Total amount of funds is $44.26 million.
Step-by-step explanation:
Given,
Donation received = $23.9 million
As it represents 54% of charity.
Let,
Total amount = x
Therefore,
54% of x = 23.9 million

Dividing both sides by 0.54

Total amount of funds is $44.26 million.
Keywords: percentage, division
Learn more about percentages at:
#LearnwithBrainly
X
1. 2x^2 - 8 = 2(x^2 - 4) = 2(x+2)(x-2)
2. 2x^2 + 8x + 6 = 2(x^2 + 4x + 3) = 2(x+3)(x+1)
3. 3n^2 + 9n -30 = 3(n^2 + 3n - 10) = 3(n+5)(n-2)
XII
1. x^2 + 2x + xy + 2y = x(x+2) + y(x+2) = (x+2)(x+y)
2. 3a^2 - 2b - 6a + ab = 3a^2 - 6a + ab - 2b = 3a(a - 2) + b(a - 2) = (a-2)(3a+b)
3. t^3 - t^2 + t - 1 = t^2(t - 1) + (t - 1) = (t-1)(t^2+1)
4. 10 + 2t - 5s - st = 10 - 5s + 2t - st = 5(2 - s) + t(2-s) = (5+t)(2-s)