MATH 225N STATISTICS FINAL EXAM
CHAMBERLAIN COLLEGE OF NURSING
EXAM SCRIPT 2026 COMPREHENSIVE
QUESTIONS WITH SOLUTIONS GRADED A+
⩥ If a confidence interval is given from 45.82 up to 55.90 and the mean
is known to be 50.86, what is the margin of error?
2.52
5.04
45.82
10.08. Answer: 5.04
⩥ If a computer manufacturer needed a supplier that could produce parts
that were very precise, what characteristics would be better?
narrow confidence interval at low confidence level
narrow confidence interval at high confidence level
wide confidence interval with high confidence level
wide confidence interval with low confidence level. Answer: narrow
confidence interval at high confidence level
⩥ Which of the following are most likely to lead to a wide confidence
interval?
,small standard deviation
small sample size
large mean
large sample size. Answer: small sample size
⩥ If you were designing a study that would benefit from data points with
high values, you would want the input variable to have:
a large sample size
a large mean
a large standard deviation
a large margin of error. Answer: a large mean
⩥ The 95% confidence interval for these parts is 56.98 to 57.05 under
normal operations. A systematic sample is taken from the manufacturing
line to determine if the production process is still within acceptable
levels. The mean of the sample is 56.99. What should be done about the
production line?
Keep the line operating as it is inside the confidence interval
Stop the line as it is inside the confidence interval
Stop the line as it is outside the confidence interval
Keep the line operating as it is outside the confidence interval. Answer:
Keep the line operating as it is inside the confidence interval
, ⩥ In a sample of 57 temperature readings taken from the freezer of a
restaurant, the mean is 29.6 degrees and the population standard
deviation is 2.7 degrees. What would be the 80% confidence interval for
the temperatures in the freezer?
(31.90, 32.44)
(29.14, 30.06)
(24.25, 35.05)
(26.91, 32.31). Answer: (29.14, 30.06)
⩥ What is the 99% confidence interval for a sample of 36 seat belts that
have a mean length of 85.6 inches long and a population standard
deviation of 2.5 inches?
(80.6, 90.6)
(83.1, 88.1)
(84.4, 86.8)
(84.5, 86.7). Answer: (84.5, 86.7)
⩥ If two samples A and B had the same mean and standard deviation,
but sample A had a larger sample size, which sample would have the
wider 95% confidence interval?
Sample B as its sample is more dispersed
Sample B as it has the smaller sample
Sample A as it comes first
CHAMBERLAIN COLLEGE OF NURSING
EXAM SCRIPT 2026 COMPREHENSIVE
QUESTIONS WITH SOLUTIONS GRADED A+
⩥ If a confidence interval is given from 45.82 up to 55.90 and the mean
is known to be 50.86, what is the margin of error?
2.52
5.04
45.82
10.08. Answer: 5.04
⩥ If a computer manufacturer needed a supplier that could produce parts
that were very precise, what characteristics would be better?
narrow confidence interval at low confidence level
narrow confidence interval at high confidence level
wide confidence interval with high confidence level
wide confidence interval with low confidence level. Answer: narrow
confidence interval at high confidence level
⩥ Which of the following are most likely to lead to a wide confidence
interval?
,small standard deviation
small sample size
large mean
large sample size. Answer: small sample size
⩥ If you were designing a study that would benefit from data points with
high values, you would want the input variable to have:
a large sample size
a large mean
a large standard deviation
a large margin of error. Answer: a large mean
⩥ The 95% confidence interval for these parts is 56.98 to 57.05 under
normal operations. A systematic sample is taken from the manufacturing
line to determine if the production process is still within acceptable
levels. The mean of the sample is 56.99. What should be done about the
production line?
Keep the line operating as it is inside the confidence interval
Stop the line as it is inside the confidence interval
Stop the line as it is outside the confidence interval
Keep the line operating as it is outside the confidence interval. Answer:
Keep the line operating as it is inside the confidence interval
, ⩥ In a sample of 57 temperature readings taken from the freezer of a
restaurant, the mean is 29.6 degrees and the population standard
deviation is 2.7 degrees. What would be the 80% confidence interval for
the temperatures in the freezer?
(31.90, 32.44)
(29.14, 30.06)
(24.25, 35.05)
(26.91, 32.31). Answer: (29.14, 30.06)
⩥ What is the 99% confidence interval for a sample of 36 seat belts that
have a mean length of 85.6 inches long and a population standard
deviation of 2.5 inches?
(80.6, 90.6)
(83.1, 88.1)
(84.4, 86.8)
(84.5, 86.7). Answer: (84.5, 86.7)
⩥ If two samples A and B had the same mean and standard deviation,
but sample A had a larger sample size, which sample would have the
wider 95% confidence interval?
Sample B as its sample is more dispersed
Sample B as it has the smaller sample
Sample A as it comes first
