Work is attached. Hope it helps!
Answer:
The mean is 19.5
Step-by-step explanation:
You have to add all of the numbers up then divide by how many numbers there are.
Ex: 5, 5, 6, 7
add them up and you get 23
Divide 23 by how many numbers you have, which in this case, is 4
The answer to this example would be 5.75
Answer:
Quadratic Equation:


From the standard form of a Quadratic Function, we get:

Discriminant:



From the discriminant, we conclude that the equation will have two real solutions.
State that:



By the way, solving the equation given:





Answer:

And using the z score given by:

Where:


If we find the z score for
we got:

So we want to find this probability:

And using the complement rule and the normal standard distribution and excel we got:

Step-by-step explanation:
For this case we have the proportion of interest given
. And we have a sample size selected n = 474
The distribution of
is given by:

We want to find this probability:

And using the z score given by:

Where:


If we find the z score for
we got:

So we want to find this probability:

And using the complement rule and the normal standard distribution and excel we got:

Minus 9 from both sides
7x = 49
X = 7