Question 1

A survey claims that 9 out of 10 doctors recommend aspirin for their patients with headaches.To
Test this claim against the alternative that the actual proportion of doctors who recommend aspirin
Is less than 0.90, a random sample of 100 doctors results in 83 who indicate that they recommend
Aspirin.The value of the test statistic in this problem is approximately equal to:

Accepted Answer

A)  - 4.12 
B)  - 2.33 
C)  - 1.86 
D)  - 0.07

Question 2

True or False: The larger the p-value, the more likely you are to reject the null hypothesis.

Accepted Answer

A) True 
 B)False

Question 3

SCENARIO 9-2
A student claims that he can correctly identify whether a person is a business major or an agriculture
major by the way the person dresses.Suppose in actuality that if someone is a business major, he can
correctly identify that person as a business major 87% of the time.When a person is an agriculture
major, the student will incorrectly identify that person as a business major 16% of the time.Presented
with one person and asked to identify the major of this person (who is either a business or an
agriculture major), he considers this to be a hypothesis test with the null hypothesis being that the
person is a business major and the alternative that the person is an agriculture major.
-Referring to Scenario 9-2, what is the value of

Accepted Answer

A)  0.13 
B)  0.16 
C)  0.84 
D)  0.87

Question 4

True or False: A sample is used to obtain a 95% confidence interval for the mean of a population.
The confidence interval goes from 15 to 19.If the same sample had been used to test the null
hypothesis that the mean of the population is equal to 18 versus the alternative hypothesis that the
mean of the population differs from 18, the null hypothesis could be rejected at a level of
significance of 0.05.

Accepted Answer

A) True 
 B)False

Question 5

True or False: For a given level of significance, if the sample size is increased but the summary
statistics remain the same, the probability of committing a Type I error will increase.

Accepted Answer

A) True 
 B)False

Question 6

The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of
The club.She would now like to determine whether or not the mean age of her customers is
Greater than 30.If so, she plans to alter the entertainment to appeal to an older crowd.If not, no
Entertainment changes will be made.Suppose she found that the sample mean was 30.45 years
And the sample standard deviation was 5 years.What is the p-value associated with the test
Statistic?

Accepted Answer

A)  0.3577 
B)  0.1423 
C)  0.0780 
D)  0.02

Question 7

An entrepreneur is considering the purchase of a coin-operated laundry.The current owner claims
That over the past 5 years, the mean daily revenue was $675 with a population standard deviation
Of $75.A sample of 30 days reveals a daily mean revenue of $625.If you were to test the null
Hypothesis that the daily mean revenue was $675 and decide not to reject the null hypothesis,
What can you conclude?

Accepted Answer

A)  There is not enough evidence to conclude that the daily mean revenue was $675. 
B)  There is not enough evidence to conclude that the daily mean revenue was not $675. 
C)  There is enough evidence to conclude that the daily mean revenue was $675. 
D)  There is enough evidence to conclude that the daily mean revenue was not $675.

Question 8

Accepted Answer

Question 9

SCENARIO 9-1
Microsoft Excel was used on a set of data involving the number of defective items found in a random
sample of 46 cases of light bulbs produced during a morning shift at a plant.A manager wants to
know if the mean number of defective bulbs per case is greater than 20 during the morning shift.She
will make her decision using a test with a level of significance of 0.10.The following information
was extracted from the Microsoft Excel output for the sample of 46 cases: 
-Referring to Scenario 9-1, what critical value should the manager use to determine the rejection
Region?

Accepted Answer

A)  1.6794 
B)  1.3011 
C)  1.3006 
D)  0.6800

Question 10

True or False: "Is the intended sample size large enough to achieve the desired power of the test
for the level of significance chosen?" should be among the questions asked when performing a
hypothesis test

Accepted Answer

A) True 
 B)False

Question 11

If an economist wishes to determine whether there is evidence that mean family income in a
Community exceeds $50,000

Accepted Answer

A)  either a one-tail or two-tail test could be used with equivalent results. 
B)  a one-tail test should be utilized. 
C)  a two-tail test should be utilized. 
D)  None of the above.

Question 12

A manager of the credit department for an oil company would like to determine whether the mean
Monthly balance of credit card holders is equal to $75.An auditor selects a random sample of 100
Accounts and finds that the mean owed is $83.40 with a sample standard deviation of $23.65.If
You were to conduct a test to determine whether the auditor should conclude that there is
Evidence that the mean balance is different from $75, which test would you use?

Accepted Answer

A)  Z-test of a population mean 
B)  Z-test of a population proportion 
C)  t-test of population mean 
D)  t-test of a population proportion

Question 13

SCENARIO 9-3
An appliance manufacturer claims to have developed a compact microwave oven that consumes a
mean of no more than 250 W.From previous studies, it is believed that power consumption for
microwave ovens is normally distributed with a population standard deviation of 15 W.A consumer
group has decided to try to discover if the claim appears true.They take a sample of 20 microwave
ovens and find that they consume a mean of 257.3 W.
-Referring to Scenario 9-3, for a test with a level of significance of 0.05, the critical value would
be ________.

Accepted Answer

The answer of SCENARIO 9-3
An appliance manufacturer claims to have...

Question 14

True or False: For a given sample size, the probability of committing a Type II error will increase
when the probability of committing a Type I error is reduced.

Accepted Answer

A) True 
 B)False

Question 15

SCENARIO 9-3
An appliance manufacturer claims to have developed a compact microwave oven that consumes a
mean of no more than 250 W.From previous studies, it is believed that power consumption for
microwave ovens is normally distributed with a population standard deviation of 15 W.A consumer
group has decided to try to discover if the claim appears true.They take a sample of 20 microwave
ovens and find that they consume a mean of 257.3 W.
-Referring to Scenario 9-3, the appropriate hypotheses to determine if the manufacturer's claim
Appears reasonable are:

Accepted Answer

Question 16

Accepted Answer

Question 17

A Type II error is committed when

Accepted Answer

A)  you reject a null hypothesis that is true. 
B)  you don't reject a null hypothesis that is true. 
C)  you reject a null hypothesis that is false. 
D)  you don't reject a null hypothesis that is false.

Question 18

Accepted Answer

Question 19

SCENARIO 9-1
Microsoft Excel was used on a set of data involving the number of defective items found in a random
sample of 46 cases of light bulbs produced during a morning shift at a plant.A manager wants to
know if the mean number of defective bulbs per case is greater than 20 during the morning shift.She
will make her decision using a test with a level of significance of 0.10.The following information
was extracted from the Microsoft Excel output for the sample of 46 cases: 
-Referring to Scenario 9-1, the parameter the manager is interested in is:

Accepted Answer

A)  the mean number of defective light bulbs per case produced at the plant. 
B)  the mean number of defective light bulbs per case among the 46 cases. 
C)  the mean number of defective light bulbs per case produced during the morning shift. 
D)  the proportion of cases with defective light bulbs produced at the plant.

Question 20

Which of the following would be an appropriate alternative hypothesis?

Accepted Answer

A)  The population proportion is less than 0.65. 
B)  The sample proportion is less than 0.65. 
C)  The population proportion is not less than 0.65. 
D)  The sample proportion is not less than 0.65.

Exam 9: Fundamentals of Hypothesis Testing: One-Sample Tests

True or False: The larger the p-value, the more likely you are to reject the null hypothesis.

True or False: For a given level of significance, if the sample size is increased but the summary statistics remain the same, the probability of committing a Type I error will increase.

True or False: "Is the intended sample size large enough to achieve the desired power of the test for the level of significance chosen?" should be among the questions asked when performing a hypothesis test

If an economist wishes to determine whether there is evidence that mean family income in a Community exceeds $50,000

True or False: For a given sample size, the probability of committing a Type II error will increase when the probability of committing a Type I error is reduced.

A Type II error is committed when

Which of the following would be an appropriate alternative hypothesis?