A student at a university wants to determine if the proportion
of students that use iPhones is less than 0.45. The hypotheses for
this scenario are as follows. Null Hypothesis: p ? 0.45,
Alternative Hypothesis: p < 0.45. If the student randomly
samples 29 other students and finds that 10 of them use iPhones,
what is the test statistic and pvalue?

1)

Test Statistic: 1.138, PValue:
0.127 


2)

Test Statistic: 1.138, PValue:
0.873 


3)

Test Statistic: 1.138, PValue:
0.127 


4)

Test Statistic: 1.138, PValue:
0.873 


5)

Test Statistic: 1.138, PValue:
0.254 

Does the average internet speed of an ISP depend on continent?
Specifically, you would like to test whether customers in North
America have an average internet download speed that is greater
than the average download speed of customers in Europe. If North
American customers are in group 1 and European customers are in
group 2, what are the hypotheses for your test of interest?

1)

H_{O}: ?_{1} >
?_{2}
H_{A}: ?_{1} ? ?_{2} 


2)

H_{O}: ?_{1} =
?_{2}
H_{A}: ?_{1} ? ?_{2} 


3)

H_{O}: ?_{1} <
?_{2}
H_{A}: ?_{1} ? ?_{2} 


4)

H_{O}: ?_{1} ?
?_{2}
H_{A}: ?_{1} > ?_{2} 


5)

H_{O}: ?_{1} ?
?_{2}
H_{A}: ?_{1} < ?_{2} 

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: ?_{D} = 0, Alternative Hypothesis:
?_{D} ? 0. If they calculate a pvalue of 0.0028 in the
paired samples ttest, what is the appropriate conclusion?

1)

The average difference in gas
mileage is equal to 0. 


2)

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


3)

We did not find enough evidence to
say the average difference in gas mileage was not 0. The additive
does not appear to have been effective. 


4)

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


5)

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