Answer: 300,000
Step-by-step explanation:
Answer:
It 20.54 round to the nearest tenth which is 20.5
Step-by-step explanation:
Answer:
A sample of 801 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
![\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=%5Cpi%20%5Cpm%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
In which
z is the z-score that has a p-value of
.
The margin of error is of:
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
95% confidence level
So
, z is the value of Z that has a p-value of
, so
.
25% of U.S. homes have a direct satellite television receiver.
This means that ![\pi = 0.25](https://tex.z-dn.net/?f=%5Cpi%20%3D%200.25)
How large a sample is necessary to estimate the true population of homes which do with 95% confidence and within 3 percentage points?
This is n for which M = 0.03. So
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
![0.03 = 1.96\sqrt{\frac{0.25*0.75}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.96%5Csqrt%7B%5Cfrac%7B0.25%2A0.75%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.96\sqrt{0.25*0.75}](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.96%5Csqrt%7B0.25%2A0.75%7D)
![\sqrt{n} = \frac{1.96\sqrt{0.25*0.75}}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.96%5Csqrt%7B0.25%2A0.75%7D%7D%7B0.03%7D)
![(\sqrt{n})^2 = (\frac{1.96\sqrt{0.25*0.75}}{0.03})^2](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E2%20%3D%20%28%5Cfrac%7B1.96%5Csqrt%7B0.25%2A0.75%7D%7D%7B0.03%7D%29%5E2)
![n = 800.3](https://tex.z-dn.net/?f=n%20%3D%20800.3)
Rounding up:
A sample of 801 is needed.
Answer: B
Step-by-step explanation:
Answer:
The math problem is easy its 8.5,9.5
Step-by-step explanation:
I know this because i am good at math