BSTAT- EXAM 3 REVIEW (updated)
questions with verified answers
To provide a range of values that, with a certain measure of confidence, contains the population
parameter of interest - correct answer ✔✔What is the purpose of calculating a confidence
interval?
Point estimate ± Margin of error - correct answer ✔✔What is the most typical form of a
calculated confidence interval?
Normality of the estimator - correct answer ✔✔Which of the following is the necessary
condition for creating confidence intervals for the population mean?
the resulting margin of error will increase and the risk of reporting an incorrect interval will
decrease - correct answer ✔✔The ages of MBA students at a university are normally distributed
with a known population variance of 10.24. Suppose you are asked to construct a 95%
confidence interval for the population mean age if the mean of a sample of 36 students is 26.5
years. If a 99% confidence interval is constructed instead of a 95% confidence interval for the
population mean, then
narrower, with the same probability of reporting an incorrect interval - correct answer ✔✔The
daily revenue from the sale of fried dough at a local street vendor in Boston is known to be
normally distributed with a known standard deviation of $120. The revenue on each of the last
25 days is noted, and the average is computed as $550. A 95% confidence interval is constructed
for the population mean revenue. If the data from the last 40 days had been used, then the
resulting 95% confidence intervals would have been
If the population standard deviation is greater, the interval is wider. - correct answer ✔✔For a
given confidence level and sample size, which of the following is true in the interval estimation
of the population mean when σ is known?
questions with verified answers
To provide a range of values that, with a certain measure of confidence, contains the population
parameter of interest - correct answer ✔✔What is the purpose of calculating a confidence
interval?
Point estimate ± Margin of error - correct answer ✔✔What is the most typical form of a
calculated confidence interval?
Normality of the estimator - correct answer ✔✔Which of the following is the necessary
condition for creating confidence intervals for the population mean?
the resulting margin of error will increase and the risk of reporting an incorrect interval will
decrease - correct answer ✔✔The ages of MBA students at a university are normally distributed
with a known population variance of 10.24. Suppose you are asked to construct a 95%
confidence interval for the population mean age if the mean of a sample of 36 students is 26.5
years. If a 99% confidence interval is constructed instead of a 95% confidence interval for the
population mean, then
narrower, with the same probability of reporting an incorrect interval - correct answer ✔✔The
daily revenue from the sale of fried dough at a local street vendor in Boston is known to be
normally distributed with a known standard deviation of $120. The revenue on each of the last
25 days is noted, and the average is computed as $550. A 95% confidence interval is constructed
for the population mean revenue. If the data from the last 40 days had been used, then the
resulting 95% confidence intervals would have been
If the population standard deviation is greater, the interval is wider. - correct answer ✔✔For a
given confidence level and sample size, which of the following is true in the interval estimation
of the population mean when σ is known?
