Answer: (6 , 3)
Step-by-step explanation: Given
x + 3y =15 ------- equation 1
4x + 2y = 30 --------- equation 2
x = 15 - 3y
Put value of x in equation 2
4 (15 - 3y) + 2y = 30
60 - 12y + 2y = 30
-10y = -30
divide by '-10' on both sides
y = 3
now, put value of y in equation 1
x + 3(3) = 15
x + 9 = 15
x = 15 - 9
x = 6
So , (x , y) = (6 , 3)
Answer:
x = - 3
Step-by-step explanation:
g(x) = 4x + 1...... (1)
g(x) = -11.... (2)
From equations (1) & (2)
-11 = 4x + 1
-11 - 1 = 4x
-12 = 4x
-12/4 = x
-3 = x
x = - 3
The inequality is < because the equal sign is an equality.
I don’t need a brai
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:
