Author Question: When constructing a confidence interval for the population mean and the standard deviation of the ... (Read 36 times)

daltonest1984

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When constructing a confidence interval for the population mean and the standard deviation of the sample is used, the degrees of freedom for the t distribution equals
 a. n-1
  b. n
  c. 29
  d. 30

Question 2

It is known that the population variance equals 484 . With a 0.95 probability, the sample size that needs to be taken if the desired margin of error is 5 or less is
 a. 25
  b. 74
  c. 189
  d. 75



Jayson

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Answer to Question 1

A

Answer to Question 2

D



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