What sample size is needed to give a margin of error within ±3 in estimating a population mean with 90% confidence, assuming a previous sample had s=20 Round your answer up to the nearest integer.

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A: (a) State the hypotheses.

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A: Given data: Margin of error  = 5% = 0.05 Confidence level  = 0.90 To find: Sample size (n) = ?

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Q: How large a sample should be selected to provide a 95% confidence interval with a margin of error of…

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A: Given data, E=2%=0.02 Let p=0.50 z-value at 95% confidence is Zc=1.96 n=?

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Q: Find a Confidence interval for the true Population Proportions if n = 30,        x = 75, and the…

A: From the given information, X=75 and n=30.

Q: The proportion of Americans who have frequent migraines is 15.2% according to the CDC. An…

A: a).The hypothesis to be tested here is- H0:p=0.152H1:p<0.152 b). Here, X=31 n=260 Therefore the…

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A:

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A: We have to identify trueness of statement.

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