Answer:
A)n= 703.96
B)n= 602.308
Step by step Explanation:
Given that you want to be 99% confident that the sample percentage is within 3.1 percentage points of the true population percentage.
Then z/2 = 1.645
And M = 3.1% = 0.031
A)Nothing is known therefore,
p = q = 0.50
E=0.031
For 90% confidence, z = 1.645
n = (zα/₂)²(p)(1-p)/M²
n= 1.645²× 0.5 × 0.5/0.031²
n= 703.96
Therefore, 703.96randomly selected air passengers must be surveyed to be 99%
B)we know that recent surveys surgest that about 38% of all air passengers prefer an aisle seat, thus p = 35% = 0.35
n = (zα/₂)²(p)(1-p)/M²
n= (1.645²× 0.31 × 0.69)/0.031²
n= 602.308
Hence, 602.308 randomly selected air passengers must be surveyed to be 90% confident that the sample percentage is within 3.1 percentage points of the true population percentage.
Answer: 368
Step-by-step explanation: 80 divided by 5 is 16, so you would use 16 to find out how many students there are. To do that, you have to do 23 times 16, which is 368. Hope this helps!
Answer:
300 dollars
Step-by-step explanation:
250 x 0.2= 50
250 + 50=300
Answer:
5 batteries.
Explanation:
"How many batteries lasted more than 5 1/2 hours?" which means it's counting not only 5 1/2, but 5 3/4 and 6 1/4
The 90% , 99% confidence interval for the population mean is 32.145 < 
< 35.855 and 31.093 < < 36.907
<h3>What is Probability ?</h3>
Probability is the study of likeliness of an event to happen.
It is given that
Total Population = 50
Mean = 35
The confidence interval is given by
is the mean
z is the confidence level value
s is the standard deviation
n is the population width
(a) The 90% confidence interval for the population mean
90% 
= 0.05
Z = 1.64
34 
1.64 * 8 / √50
34 1.855
32.145 < < 35.855
(b) The 99% confidence interval for the population mean
99% = 0.005
Z=2.57
34 2.57 * 8 / √50
34 2.907
31.093 < < 36.907
Therefore the confidence interval for population mean has been determined.
The complete question is
A simple random sample of 50 items from a population width =7 resulted in a sample mean of 35. If required, round your answers to two decimal places.
a. Provide a 90% confidence interval for the population mean
b. Provide a 99% confidence interval for the population mean
To know more about Probability
brainly.com/question/11234923
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