Z-distribution.docx - Construct a 90% confidence interval...

Construct a 90% confidence interval for a sampling distribution having means of {4, 4, 4, 4.2, 4.2, 4.3,
4.3, 4.3, 4.4, 4.4, 4.4, 4.4, 4.5, 4.5, 4.6, 4.7, 4.7, 4.7, 4.8, 4.8, 4.8, 4.9, 4.9, 4.9, 4.9, 5, 5, 5, 5, 5, 5, 5.1, 5.1,
5.1, 5.2, 5.2}. The standard deviation of the population from which these samples were drawn was
known to be: ơ =0.357.
4.558 to 4.792
10% to 90%
4.567 to 4.783
4.577 to 4.773
Construct a 95% confidence interval for a sampling distribution having means of {4, 4, 4, 4.2, 4.2, 4.3,
4.3, 4.3, 4.4, 4.4, 4.4, 4.4, 4.5, 4.5, 4.6, 4.7, 4.7, 4.7, 4.8, 4.8, 4.8, 4.9, 4.9, 4.9, 4.9, 5, 5, 5, 5, 5, 5, 5.1, 5.1,
5.1, 5.2, 5.2}. The standard deviation of the population from which these samples were drawn was
known to be: ơ =0.357.
4.577 to 4.773
5% to 95%
4.567 to 4.783
4.558 to 4.792
Which of the following is a characteristic of the Z-test?
Follows a Z-distribution
More adaptable than t-test
Always uses a normal distribution and applied when standard deviation is known
What is the first step in finding the calculation of a confidence interval?
Calculate the sample Mean
Which of the following is a characteristic of the Z-test?

Preferred when standard deviations are known
As the confidence interval increases for the same sampling distribution, the absolute value of the
critical value ___________.
remains the same
increases
decreases
becomes smaller
Construct a 90% confidence interval for a sampling distribution having a mean of 25 and a size of
64. The standard deviation of the population from which the samples are drawn is 4.
24.02 to 25.98
24.178 to 25.822
24.094 to 25.906
10% to 90%
Which of the following is a characteristic of the Z-test?
In which of the following, do we use Z-distribution?