Question 5 (1 point)
You are interested in getting an investment portfolio started
with any extra money you make from your part time job while also
going to school. While flipping through the latest edition of Money
magazine, you read an article that of a survey of magazine
subscribers, 194 were randomly selected and analyzed. A 95%
confidence interval was constructed for the proportion of all
subscribers who made money in the previous year in their
investments, which was ( 0.777 , 0.8828 ). What is the correct
interpretation of this confidence interval?
Question 5 options:

1)

We are certain that 95% of subscribers made
between 0.777 and 0.8828. 


2)

We cannot determine the proper
interpretation of this interval. 


3)

We are 95% confident that the proportion of
all Money magazine subscribers that made money in the previous year
from their investments is between 0.777 and 0.8828. 


4)

We are 95% confident that the proportion of
all Money magazine subscribers sampled that made money in the
previous year from their investments is between 0.777 and
0.8828. 


5)

We are 95% confident that of the 194
respondents, between 0.777 and 0.8828 of them made more than they
lost. 

Question 6 (1 point)
Suppose you want to determine the average height of college
basketball players in NCAA Division I. In a random sample of 12
players, the sample average is 73.608 inches with a standard
deviation of 5.7866 inches. What is the 95% confidence interval for
the average height of all NCAA DI players?
Question 6 options:
Question 7 (1 point)
Suppose that you are the director of table game operations at a
large casino, known especially for its poker room. You are
interested in determining the average number of hands the casino
should expect per hour during peak hours in the poker room. You
monitor the number of hands over the next week and given a random
sample of 22 hours, you see that on average 178.3 hands are played
per hour, with a standard deviation of 9.78 hands and you
calculated a 99% confidence interval to be (172.4, 184.2). Your
manager believes the true mean is 141.7. Which of the following is
the best conclusion?
Question 7 options:

1)

The average number of hands played per hour
is not significantly different from 141.7 


2)

The percentage of hours in which more than
141.7 hands of poker are played is 99%. 


3)

We cannot determine the proper
interpretation based on the information given. 


4)

We are 99% confident that the average
number of hands played per hour is greater than 141.7. 


5)

We are 99% confident that the average
number of hands played per hour is less than 141.7. 

Question 8 (1 point)
In a packing plant, one of the machines packs jars into a box. A
sales rep for a packing machine manufacturer comes into the plant
saying that a new machine he is selling will pack the jars faster
than the old machine. To test this claim, each machine is timed for
how long it takes to pack 10 cartons of jars at randomly chosen
times. Given a 90% confidence interval of (0.51, 6.95) for the
true difference in average times to pack the jars (old machine 
new machine), what can you conclude from this interval?
Question 8 options:

1)

We are 90% confident that the average
packing time of the new machine is greater than the old machine.
The sales rep does not appear to be telling the truth. 


2)

We are 90% confident that the average
packing time of the old machine is greater than the new machine.
The sales rep appears to be correct. 


3)

We are 90% confident that the difference
between the two sample means falls within the interval. 


4)

There is no significant difference between
the average packing times of the two machines. The sales rep does
not appear to be telling the truth. 


5)

We do not have enough information to make a
conclusion. 
