A simple random sample of size
E Click the icon to view the table of areas under the t-distribution.
(a) Construct a
Lower bound: 16.69 ; Upper bound: 19.91
(Use ascending order. Round to two decimal places as needed.)
(b) Construct a
Lower bound: 17.03 ; Upper bound: 19.57
(Use ascending order. Round to two decimal places as needed.)
How does increasing the sample size affect the margin of error, E?
A. The margin of error decreases.
B. The margin of error increases.
C. The margin of error does not change.
(c) Construct a
Lower bound: 16.14 '; Upper bound: 20.46 '
(Use ascending order. Round to two decimal places as needed.)
Compare the results to those obtained in part (a). How does increasing the level of confidence affect the size of the margin of error,
A. The margin of error increases.
B. The margin of error decreases.
C. The margin of error does not change.
(d) If the sample size is 17 , what conditions must be satisfied to compute the confidence interval?
A. The sample data must come from a population that is normally distributed with no outliers.
B. The sample must come from a population that is normally distributed and the sample size must be large.
C. The sample size must be large and the sample should not have any outliers.
The 95% confidence interval for the population mean when the sample size is 34 is approximately
Step 1 :Given that the sample mean,
Step 2 :The formula for the confidence interval is
Step 3 :Look up the t-score for a 95% confidence interval with 33 degrees of freedom (which is
Step 4 :Calculate the margin of error, which is
Step 5 :Calculate the lower bound of the confidence interval, which is
Step 6 :Calculate the upper bound of the confidence interval, which is
Step 7 :The 95% confidence interval for the population mean when the sample size is 34 is approximately