Answer:
19.30
Step-by-step explanation:
if your finding the discounted price, you'd take 20% and turn it into .20 and then subtract 19.50 and .20
Using the z-distribution, it is found that a sample size of 1066 is required.
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:
![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)
From the previous study, the estimate is of 0.23, hence
.
98% confidence level, hence
, z is the value of Z that has a p-value of
, so
.
The sample size is <u>n for which M = 0.03</u>, hence:
![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 = 2.327\sqrt{\frac{0.23(0.77)}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%202.327%5Csqrt%7B%5Cfrac%7B0.23%280.77%29%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 2.327\sqrt{0.23(0.77)}](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%202.327%5Csqrt%7B0.23%280.77%29%7D)
![\sqrt{n} = \left(\frac{2.327\sqrt{0.23(0.77)}}{0.03}\right)](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cleft%28%5Cfrac%7B2.327%5Csqrt%7B0.23%280.77%29%7D%7D%7B0.03%7D%5Cright%29)
![(\sqrt{n})^2 = \left(\frac{2.327\sqrt{0.23(0.77)}}{0.03}\right)^2](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E2%20%3D%20%5Cleft%28%5Cfrac%7B2.327%5Csqrt%7B0.23%280.77%29%7D%7D%7B0.03%7D%5Cright%29%5E2)
![n = 1065.5](https://tex.z-dn.net/?f=n%20%3D%201065.5)
Rounding up, a sample size of 1066 is required.
A similar problem is given at brainly.com/question/12517818
Answer:
No solution
Step-by-step explanation:
Let's solve using substitution (substitute 15x+2 for y):
-15x+15x+2=1
2=1
No solution
Another method...
Since these lines have the same slope, but different y-intercepts, they are parallel. This means they will not intersect therefore there is...
No solution
Answer:
Step-by-step explanation:
n+8+6
Answer:9.25
Step-by-step explanation: