DEVRY UNIVERSITY KELLER GRADUATE
SCHOOL OF MANAGEMENT REVIEW STUDY
SHEET 2026 ACCURATE RESPONSES FULL
SOLUTION
◉ Market research indicates that a new product has the potential to
make the company an additional $1.6 million, with a standard
deviation of $2.0 million. If these estimates were based on a sample
of 8 customers from a normally distributed data set, what would be
the 95% confidence interval?
(0.00, 3.27)
(0.21, 3.00)
(-0.40, 3.60)
(-0.07, 3.27) Answer: (-0.07, 3.27)
◉ In a sample of 28 cups of coffee at the local coffee shop, the
temperatures were normally distributed with a mean of 182.5
degrees with a sample standard deviation of 14.1 degrees. What
would be the 95% confidence interval for the temperature of your
cup of coffee?
(177.28, 187.72)
(177.03, 187.97)
(168.40, 196.60)
,(148.40, 176.60) Answer: (177.03, 187.97)
◉ In a situation where the sample size was 28 while the population
standard deviation was increased, what would be the impact on the
confidence interval?
It would become narrower due to using the t distribution
It would become wider with more dispersion in values
It would widen with more values
It would become wider due to using the z distribution Answer: It
would become wider with more dispersion in values
◉ You needed a supplier that could provide parts as close to 76.8
inches in length as possible. You receive four contracts, each with a
promised level of accuracy in the parts supplied. Which of these four
would you be most likely to accept?
Mean of 76.8 with a 99% confidence interval of 76.6 to 77.0
Mean of 76.800 with a 99% confidence interval of 76.5 to 77.1
Mean of 76.8 with a 95% confidence interval of 76.6 to 77.0
Mean of 76.800 with a 90% confidence interval of 76.6 to 77.0
Answer: Mean of 76.8 with a 99% confidence interval of 76.6 to 77.0
◉ From a random sample of 55 businesses, it is found that the mean
time that employees spend on personal issues each week is 4.9
, hours with a standard deviation of 0.35 hours. What is the 95%
confidence interval for the amount of time spent on personal issues?
(4.84, 4.96)
(4.82, 4.98)
(4.83, 4.97)
(4.81, 4.99) Answer: (4.81, 4.99)
◉ If a confidence interval is given from 8.52 to 10.23 and the mean is
known to be 9.375, what is the maximum error?
0.428
1.710
0.855
8.520 Answer: 0.855
◉ Which of the following is most likely to lead to a large margin of
error?
small mean
large sample size
small sample size
small standard deviation Answer: small sample size
◉ From a random sample of 41 teens, it is found that on average
they spend 31.8 hours each week online with a population standard
SCHOOL OF MANAGEMENT REVIEW STUDY
SHEET 2026 ACCURATE RESPONSES FULL
SOLUTION
◉ Market research indicates that a new product has the potential to
make the company an additional $1.6 million, with a standard
deviation of $2.0 million. If these estimates were based on a sample
of 8 customers from a normally distributed data set, what would be
the 95% confidence interval?
(0.00, 3.27)
(0.21, 3.00)
(-0.40, 3.60)
(-0.07, 3.27) Answer: (-0.07, 3.27)
◉ In a sample of 28 cups of coffee at the local coffee shop, the
temperatures were normally distributed with a mean of 182.5
degrees with a sample standard deviation of 14.1 degrees. What
would be the 95% confidence interval for the temperature of your
cup of coffee?
(177.28, 187.72)
(177.03, 187.97)
(168.40, 196.60)
,(148.40, 176.60) Answer: (177.03, 187.97)
◉ In a situation where the sample size was 28 while the population
standard deviation was increased, what would be the impact on the
confidence interval?
It would become narrower due to using the t distribution
It would become wider with more dispersion in values
It would widen with more values
It would become wider due to using the z distribution Answer: It
would become wider with more dispersion in values
◉ You needed a supplier that could provide parts as close to 76.8
inches in length as possible. You receive four contracts, each with a
promised level of accuracy in the parts supplied. Which of these four
would you be most likely to accept?
Mean of 76.8 with a 99% confidence interval of 76.6 to 77.0
Mean of 76.800 with a 99% confidence interval of 76.5 to 77.1
Mean of 76.8 with a 95% confidence interval of 76.6 to 77.0
Mean of 76.800 with a 90% confidence interval of 76.6 to 77.0
Answer: Mean of 76.8 with a 99% confidence interval of 76.6 to 77.0
◉ From a random sample of 55 businesses, it is found that the mean
time that employees spend on personal issues each week is 4.9
, hours with a standard deviation of 0.35 hours. What is the 95%
confidence interval for the amount of time spent on personal issues?
(4.84, 4.96)
(4.82, 4.98)
(4.83, 4.97)
(4.81, 4.99) Answer: (4.81, 4.99)
◉ If a confidence interval is given from 8.52 to 10.23 and the mean is
known to be 9.375, what is the maximum error?
0.428
1.710
0.855
8.520 Answer: 0.855
◉ Which of the following is most likely to lead to a large margin of
error?
small mean
large sample size
small sample size
small standard deviation Answer: small sample size
◉ From a random sample of 41 teens, it is found that on average
they spend 31.8 hours each week online with a population standard
