AP STAT MCQ 6B EXAM QUESTIONS &
ANSWERS!!
A study reports that 75 percent of young adults in a county get their news from
online sources. A sociologist believes that the percentage is actually greater
than 75 percent. The sociologist will select a random sample of young adults
from around the county to interview. Which of the following is the most
appropriate method for investigating the sociologist's belief? Answer - C. A
one-sample z-test for a population proportion
A one-sample z-test for a population proportion is appropriate to investigate
whether the proportion is greater than 0.75.
A study reported that 28 percent of middle school students in a certain state
participate in community service activities. A teacher believes that the rate is
greater than 28 percent for the middle school students in the teacher's district.
The teacher selected a random sample of middle school students from the
district, and the percent of students in the sample who participated in
community service activities was found to be 32 percent. Which of the
following is the most appropriate method for investigating the teacher's belief?
Answer - D. A one-sample z-test for a population proportion
A one-sample z-test for a population proportion is appropriate to investigate
whether the proportion is greater than 0.28.
A workers' representative for a large factory believes that more than half the
workers at the factory want the opportunity to work more overtime hours.
Which of the following are the appropriate hypotheses to test the
representative's belief? Answer - E.
H0: p=0.5
, HA: p>0.5
The null hypothesis is a statement that the proportion is equal to 0.5. The
alternative hypothesis is what the representative wants to test: that the
proportion is actually greater than 0.5.
A manufacturer of cell phone screens is concerned because 12 percent of the
screens manufactured using a previous process were rejected at the final
inspection and could not be sold. A new process is introduced that is intended
to reduce the proportion of rejected screens. After the process has been in
place for several months a random sample of 100 screens is selected and
inspected. Of the 100 screens 6 are rejected. What are the appropriate
hypotheses to investigate whether the new process reduces the population
proportion of screens that will be rejected? Answer - A.
H0: p=0.12
HA: p<0.12
The null hypothesis is a statement of the population proportion of 0.12. The
alternative hypothesis is the belief that the new proportion will be less than
the current unacceptable proportion of 0.12.
A one-sample z-test for a population proportion p will be conducted. Which of
the following conditions checks that the sampling distribution of the sample
proportion is approximately normal?
I. The sample is selected at random.
II. np0≥10 and n(1−p0)≥10 for sample size n.
III. The sample size is less than or equal to 10 percent of the population size.
Answer - B. II only
ANSWERS!!
A study reports that 75 percent of young adults in a county get their news from
online sources. A sociologist believes that the percentage is actually greater
than 75 percent. The sociologist will select a random sample of young adults
from around the county to interview. Which of the following is the most
appropriate method for investigating the sociologist's belief? Answer - C. A
one-sample z-test for a population proportion
A one-sample z-test for a population proportion is appropriate to investigate
whether the proportion is greater than 0.75.
A study reported that 28 percent of middle school students in a certain state
participate in community service activities. A teacher believes that the rate is
greater than 28 percent for the middle school students in the teacher's district.
The teacher selected a random sample of middle school students from the
district, and the percent of students in the sample who participated in
community service activities was found to be 32 percent. Which of the
following is the most appropriate method for investigating the teacher's belief?
Answer - D. A one-sample z-test for a population proportion
A one-sample z-test for a population proportion is appropriate to investigate
whether the proportion is greater than 0.28.
A workers' representative for a large factory believes that more than half the
workers at the factory want the opportunity to work more overtime hours.
Which of the following are the appropriate hypotheses to test the
representative's belief? Answer - E.
H0: p=0.5
, HA: p>0.5
The null hypothesis is a statement that the proportion is equal to 0.5. The
alternative hypothesis is what the representative wants to test: that the
proportion is actually greater than 0.5.
A manufacturer of cell phone screens is concerned because 12 percent of the
screens manufactured using a previous process were rejected at the final
inspection and could not be sold. A new process is introduced that is intended
to reduce the proportion of rejected screens. After the process has been in
place for several months a random sample of 100 screens is selected and
inspected. Of the 100 screens 6 are rejected. What are the appropriate
hypotheses to investigate whether the new process reduces the population
proportion of screens that will be rejected? Answer - A.
H0: p=0.12
HA: p<0.12
The null hypothesis is a statement of the population proportion of 0.12. The
alternative hypothesis is the belief that the new proportion will be less than
the current unacceptable proportion of 0.12.
A one-sample z-test for a population proportion p will be conducted. Which of
the following conditions checks that the sampling distribution of the sample
proportion is approximately normal?
I. The sample is selected at random.
II. np0≥10 and n(1−p0)≥10 for sample size n.
III. The sample size is less than or equal to 10 percent of the population size.
Answer - B. II only
