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2 years ago

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The Office of Student Services at UNC would like to estimate the proportion of UNC's 34,000 students who are foreign students. I

n their random sample of 50 students, 4 are foreign students. Unknown to them, the proportion of all UNC students that are foreign students is 0.061. For each student, let x=0 if the student is from the U.S.
Find the mean and the standard deviation of the sampling distribution of the sample proportion for a sample of size 50.

1 answer:

Roman55 [17]2 years ago

3 0

Answer:

Step-by-step explanation:

Given that the Office of Student Services at UNC would like to estimate the proportion of UNC's 34,000 students who are foreign students.

In their random sample of 50 students, 4 are foreign students.

Sample proportion = $\frac{4}{50} =0.08$

the proportion of all UNC students that are foreign students is 0.061.

i.e. Population proportion= 0.061

Mean for 50 size sample = sample proportion = 0.08

Std deviation of sample proportion = $\sqrt{0.061(1-0.061)/50} \\=0.0338$

Hence for the ampling distribution of the sample proportion for a sample of size 50, mean =0.08 and std dev = 0.0338

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Answer:

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Step-by-step explanation:

see the attached figure to better understand the problem

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Answer:

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Step-by-step explanation:

From the question we are told that

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The standard deviation is $\sigma = 0.2$

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Here

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Step-by-step explanation:

Previous concepts

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$z_{\alpha/2}=1.64$

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