Answer:
We need to select at least 1068 sales transactions.
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 zscore that has a pvalue 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)
95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
How many randomly selected sales transactions must be surveyed to determine the percentage that transpired over the Internet?
We need to survey at least n sales transactions.
Within three percentage points, so M = 0.03.
We do not know the population proportion, so we estimate it at
, which is when we are going to need the largest sample size.
![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{0.5*0.5}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.96%5Csqrt%7B%5Cfrac%7B0.5%2A0.5%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.96*0.5](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.96%2A0.5)
![\sqrt{n} = \frac{1.96*0.5}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.96%2A0.5%7D%7B0.03%7D)
![(\sqrt{n})^{2} = (\frac{1.96*0.5}{0.03})^{2}](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E%7B2%7D%20%3D%20%28%5Cfrac%7B1.96%2A0.5%7D%7B0.03%7D%29%5E%7B2%7D)
![n = 1067.1](https://tex.z-dn.net/?f=n%20%3D%201067.1)
Rounding up
1068
We need to select at least 1068 sales transactions.
Answer:
Prediction is not correct.
Step-by-step explanation:
We are given the following in the question:
Percentage of emails that come back undelivered = 3%
Total number of emails = 12,372
Number of undelivered notice = 437
Verification:
![3\%\times 12372\\\\=\dfrac{3}{100}\times 12372\\\\=371.16\\\neq 437](https://tex.z-dn.net/?f=3%5C%25%5Ctimes%2012372%5C%5C%5C%5C%3D%5Cdfrac%7B3%7D%7B100%7D%5Ctimes%2012372%5C%5C%5C%5C%3D371.16%5C%5C%5Cneq%20437)
He will receive approximately 371 undelivered email.
Thus, the prediction that editor will receive 437 notices for undelivered email is not correct.
Answer:
0000000000.00001
Step-by-step explanation:
7ycf6gffty
Answer:
1/ x = 22.5°
2/ x = 60°
Step-by-step explanation:
1/ We have: 3x + 2x + 3x = 180°
=> 8x = 180° => x = 22.5°
2/ We have: x + x + x = 3x = 180°
=> x = 60°
1. Proof
1. Proofln(x) dx. set. u = ln(x), dv = dx. then we find. du = (1/x) dx, v = x.
1. Proofln(x) dx. set. u = ln(x), dv = dx. then we find. du = (1/x) dx, v = x.substitute. ln(x) dx = u dv.
1. Proofln(x) dx. set. u = ln(x), dv = dx. then we find. du = (1/x) dx, v = x.substitute. ln(x) dx = u dv.and use integration by parts. = uv - v du.
1. Proofln(x) dx. set. u = ln(x), dv = dx. then we find. du = (1/x) dx, v = x.substitute. ln(x) dx = u dv.and use integration by parts. = uv - v du.substitute u=ln(x), v=x, and du=(1/x)dx.
hope this will help u