Answer:
A and D
Step-by-step explanation:
Here, we shall be evaluating the validity of the statements;
A. Yes, A is true
There are four even numbers 2,4,6 and 8 and 4 odd number 1,3,5,7; The landing should be equal at 125 each
B. This is wrong
It is supposed to land half of the number of time s which is half of 250 and that is 125
C.This is wrong
The numbers greater than 4 are 5,6,7,8
Now, the probability should be 4/8 = 1/2 and that is 50%
D. This is correct
Number of times we have a landing on odd numbers is 250-135 = 115
The experimental probability of landing on an odd number is thus 115/250 = 0.46 which is 46%
Answer:

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

And replacing we got:

The variance is calculated with this formula:
![Var(X) = E(X^2) -[E(X)]^2 = 0.33 -(0.15)^2 = 0.3075](https://tex.z-dn.net/?f=%20Var%28X%29%20%3D%20E%28X%5E2%29%20-%5BE%28X%29%5D%5E2%20%3D%200.33%20-%280.15%29%5E2%20%3D%200.3075)
And the standard deviation is just the square root of the variance and we got:

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
LEt X the random variable who represent the number of defective transistors. For this case we have the following probability distribution for X
X 0 1 2 3
P(X) 0.92 0.03 0.03 0.02
We can calculate the expected value with the following formula:

And replacing we got:

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

And replacing we got:

The variance is calculated with this formula:
![Var(X) = E(X^2) -[E(X)]^2 = 0.33 -(0.15)^2 = 0.3075](https://tex.z-dn.net/?f=%20Var%28X%29%20%3D%20E%28X%5E2%29%20-%5BE%28X%29%5D%5E2%20%3D%200.33%20-%280.15%29%5E2%20%3D%200.3075)
And the standard deviation is just the square root of the variance and we got:

Answer:
∡BCE = 60
Step-by-step explanation:
Here, we want to find the angle marked BCE
From our diagram, the angle marked BCE is y
Looking at triangle BCE, we have the right angle, an angle measure of 30 and the angle marked y which we say is BCE
mathematically, the sum of all these will give 180 as the sum f the interior angles of a triangle is 180
Thus, we have that;
y + 30 + 90 = 180
y = 180-120
y = 60
Answer:
14
Step-by-step explanation:
Caitlin buys twice as many apples as oranges.

Apples cost 0.25 and Oranges cost 0.30, we have a maximum of 5 to spend.

