****PLEASE ANSWER ALL QUESTIONS****
Question 12 (1 point)
A medical researcher wants to determine if the average hospital
stay of patients that undergo a certain procedure is greater than
8.7 days. The hypotheses for this scenario are as follows: Null
Hypothesis: μ ≤ 8.7, Alternative Hypothesis: μ > 8.7. If the
researcher takes a random sample of patients and calculates a
pvalue of 0.0942 based on the data, what is the appropriate
conclusion? Conclude at the 5% level of significance.
Question 12 options:

1)

We did not find enough evidence to say the true average
hospital stay of patients is shorter than 8.7 days. 


2)

The true average hospital stay of patients is significantly
longer than 8.7 days. 


3)

We did not find enough evidence to say the true average
hospital stay of patients is longer than 8.7 days. 


4)

The true average hospital stay of patients is shorter than or
equal to 8.7 days. 


5)

We did not find enough evidence to say a significant difference
exists between the true average hospital stay of patients and 8.7
days. 

Question 13 (1 point)
Suppose you work for a political pollster during an election
year. You are tasked with determining the projected winner of the
November election. That is, you wish to determine if the number of
votes for Candidate 1 is different from the votes for Candidate 2.
What are the hypotheses for this test?
Question 13 options:

1)

H_{O}: μ_{1} > μ_{2}
H_{A}: μ_{1} ≤ μ_{2} 


2)

H_{O}: μ_{1} ≥ μ_{2}
H_{A}: μ_{1} < μ_{2} 


3)

H_{O}: μ_{1} ≠ μ_{2}
H_{A}: μ_{1} = μ_{2} 


4)

H_{O}: μ_{1} ≤ μ_{2}
H_{A}: μ_{1} > μ_{2} 


5)

H_{O}: μ_{1} = μ_{2}
H_{A}: μ_{1} ≠ μ_{2} 

Question 14 (1 point)
The owner of a local golf course wants to examine the difference
between the average ages of males and females that play on the golf
course. Specifically, he wants to test is if the average age of
males is greater than the average age of females. Assuming males
are considered group 1 and females are group 2, this means the
hypotheses he wants to tests are as follows: Null Hypothesis:
μ_{1} ≤ μ_{2}, Alternative Hypothesis:
μ_{1} > μ_{2}. He randomly samples 30 men and 26
women that play on his course. He finds the average age of the men
to be 34.26 with a standard deviation of 16.767. The average age of
the women was 30.53 with a standard deviation of 18.195. If the
owner conducts a hypothesis test, what is the test statistic and
what is the pvalue? Assume the population standard deviations are
the same.
Question 14 options:

1)

Test Statistic: 0.798, PValue: 0.4284 


2)

Test Statistic: 0.798, PValue: 0.2142 


3)

Test Statistic: 0.798, PValue: 0.2142 


4)

Test Statistic: 0.798, PValue: 0.7858 


5)

Test Statistic: 0.798, PValue: 0.7858 

Question 15 (1 point)
It is believed that students who begin studying for final exams
a week before the test score differently than students who wait
until the night before. Suppose you want to test the hypothesis
that students who study one week before score different from
students who study the night before. A hypothesis test for two
independent samples is run based on your data and a pvalue is
calculated to be 0.7073. What is the appropriate conclusion?
Question 15 options:

1)

The average score of students who study one week before a test
is equal to the average score of students who wait to study until
the night before a test. 


2)

We did not find enough evidence to say the average score of
students who study one week before a test is less than the average
score of students who wait to study until the night before a
test. 


3)

We did not find enough evidence to say the average score of
students who study one week before a test is greater than the
average score of students who wait to study until the night before
a test. 


4)

The average score of students who study one week before a test
is significantly different from the average score of students who
wait to study until the night before a test. 


5)

We did not find enough evidence to say a significant difference
exists between the average score of students who study one week
before a test and the average score of students who wait to study
until the night before a test. 

Question 16 (1 point)
A new gasoline additive is supposed to make gas burn more
cleanly and increase gas mileage in the process. Consumer
Protection Anonymous conducted a mileage test to confirm this. They
took a sample of their cars, filled it with regular gas, and drove
it on I94 until it was empty. They repeated the process using the
same cars, but using the gas additive. Using the data they found,
they performed a paired ttest with data calculated as (with
additive  without additive) with the following hypotheses: Null
Hypothesis: μ_{D} ≥ 0, Alternative Hypothesis:
μ_{D} < 0. If they calculate a pvalue of 0.0109 in the
paired samples ttest, what is the appropriate conclusion?
Question 16 options:

1)

The average difference in gas mileage is significantly less
than 0. The average gas mileage was higher without the
additive. 


2)

We did not find enough evidence to say there was a
significantly negative average difference in gas mileage. The
additive does not appear be effective. 


3)

The average difference in gas mileage is greater than or equal
to 0. 


4)

The average difference in gas mileage is significantly
different from 0. There is a significant difference in gas mileage
with and without the additive. 


5)

The average difference in gas mileage is significantly larger
than 0. The average gas mileage was higher with the additive. 

Question 17 (1 point)
In the year 2000, the average car had a fuel economy of 20.9
MPG. You are curious as to whether the average in the present day
is less than the historical value. The hypotheses for this scenario
are as follows: Null Hypothesis: μ ≥ 20.9, Alternative Hypothesis:
μ < 20.9. If the true average fuel economy today is 22.1 MPG and
the null hypothesis is not rejected, did a type I, type II, or no
error occur?
Question 17 options:

1)

We do not know the pvalue, so we cannot determine if an error
has occurred. 


2)

Type I Error has occurred. 


3)

No error has occurred. 


4)

We do not know the degrees of freedom, so we cannot determine
if an error has occurred. 


5)

Type II Error has occurred 
