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bachelor in business administration
Polytechnic State University Sanluis
Jan-2006 - Nov-2010
CPA
Polytechnic State University
Jan-2012 - Nov-2016
Professor
Harvard Square Academy (HS2)
Mar-2012 - Present
18.     A population has a mean of 200 and a standard deviation of 50. A simple random sample of size 100 will be taken and the sample mean x¯ will be used to estimate the population mean.
a.      What is the expected value of x¯?
b.      What is the standard deviation of x¯?
c.      Show the sampling distribution of x¯.
d.      What does the sampling distribution of x¯ show?
19.     A population has a mean of 200 and a standard deviation of 50. Suppose a simple random sample of size 100 is selected and x¯ is used to estimate μ.
a.      What is the probability that the sample mean will be within ±5 of the population mean?
b.      What is the probability that the sample mean will be within ±10 of the population mean?
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