Answer:
Step-by-step explanation:
Hello!
Your study variable is X: "number of ColorSmart-5000 that didn't need repairs after 5 years of use, in a sample of 390"
X~Bi (n;ρ)
ρ: population proportion of ColorSmart-5000 that didn't need repairs after 5 years of use. ρ = 0.95
n= 390
x= 303
sample proportion ^ρ: x/n = 303/390 = 0.776 ≅ 0.78
Applying the Central Limit Theorem you approximate the distribution of the sample proportion to normal to obtain the statistic to use.
You are asked to estimate the population proportion of televisions that didn't require repairs with a confidence interval, the formula is:
^ρ± * √[(^ρ(1-^ρ))/n]
* √[(^ρ(1-^ρ))/n]
 =
 =  = 2.58
 = 2.58
0.78±2.58* √[(0.78(1-0.78))/390]
0.0541
[0.726;0.834]
With a confidence level of 99% you'd expect that the interval [0.726;0.834] contains the true value of the proportion of ColorSmart-5000 that didn't need repairs after 5 years of use.
I hope it helps!
 
        
             
        
        
        
Answer:
vertex = (- 1, 3 )
Step-by-step explanation:
Given a parabola in standard form
y = ax² + bx + c ( a ≠ 0 )
Then the x- coordinate of the vertex is
 = -
 = - 
y = 2x² + 4x + 5 ← is in standard form
with a = 2, b = 4, then
 = -
 = -  = - 1
 = - 1
Substitute x = - 1 into the equation for corresponding value of y, that is
y = 2(- 1)² + 4(- 1) + 5 = 2 - 4 + 5 = 3
vertex = (- 1, 3 )
 
        
             
        
        
        
Answer:  The total number of  pizzas that can be made from the given choices is 24.
Step-by-step explanation:  Given that a pizza parlor offers 3 sizes of pizzas, 2 types of crust, and one of 4 different toppings.
We are to find the number of different pizzas that can be made from the given choices.
We have the <em><u>COUNTING PRINCIPLE :</u></em>
If we have m ways of doing one task and n ways of doing the second task, then the number of ways in which we can do both the tasks together is m×n.
Therefore, the number of different pizzas that can be made from the given choices is

Thus, the total number of  pizzas that can be made from the given choices is 24.