MATH 225N
Week 8 Final Exam
,QUESTION 1
Of the following pairs of events, which pair has mutually exclusive events?
rolling a sum greater than 7 from two rolls of a standard die and rolling
a 4 for the first throw
drawing a 2 and drawing a 4 with replacement from a standard deck of
cards rolling a sum of 9 from two rolls of a standard die and rolling a 2 for
the first roll drawing a red card and then drawing a black card with
replacement from a standard
deck of cards
QUESTION 2
Hugo averages 41 words per minute on a typing test with a standard
deviation of 7.5 words per minute. Suppose Hugo's words per minute
on a typing test are normally distributed. Let X= the number of words
per minute on a typing test.
Then, X∼N(41,7.5).
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z-score when x=45 is . This z-
score tells you that x=45 is standard
deviations to the (right/left) of the mean, .
Correctly fill in the blanks in the statement
above. Select the correct answer below:
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is −0.533. This z-score tells you that x=45 is 0.533
standard deviations to the left of the mean, 41.
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is −0.381. This z-score tells you that x=45 is 0.381
standard deviations to the left of the mean, 41.
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is 0.381. This z-score tells you that x=45 is 0.381
standard deviations to the right of the mean, 41.
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is 0.533. This z-score tells you that x=45 is 0.533
standard deviations to the right of the mean, 41.
,QUESTION 3
A fitness center claims that the mean amount of time that a person spends
33 minutes. Identify the null hypothesis, H0, and the
at the gym per visit is
alternative hypothesis, Ha, in terms of the parameter μ.
Select the correct answer below:
H0: μ≠33; Ha:
μ=33 H0: μ=33;
Ha: μ≠33 H0:
μ≥33; Ha: μ<33
H0: μ≤33; Ha:
μ>33
QUESTION 4
A recent study suggested that 81% of senior citizens take at least one
prescription medication. Amelia is a nurse at a large hospital who would
like to know whether the
percentage is the same for senior citizen patients who go to her hospital.
She randomly selects 59 senior citizens patients who were treated at the
hospital and finds
that 49 of them take at least one prescription medication. What are the null
and alternative hypotheses for this hypothesis test?
{H0:p=0.81Ha:p>0.81
{H0:p≠0.81Ha:p=0.81
{H0:p=0.81Ha:p<0.81
{H0:p=0.81Ha:p≠0.81
QUESTION 5
, A doctor notes her patient's temperature in degrees Fahrenheit every hour to make
sure the patient does not get a fever. What is the level of measurement of the data.
nomin
al
ordinal
interva
l ratio
QUESTION 6
Assume the null hypothesis, H0, is: Jacob earns enough money to afford a luxury
apartment. Find the Type I error in this scenario.
Jacob thinks he does not earn enough money to afford the luxury apartment
when, in fact, he does.
Jacob thinks he does not earn enough money to afford the luxury apartment
when, in fact, he does not.
Jacob thinks he earns enough money to afford the luxury apartment when, in
fact, he does
not.
Jacob thinks he earns enough money to afford the luxury apartment when, in
fact, he does.
QUESTION 7
The population standard deviation for the heights of dogs, in
inches, in a city is 3.7 inches. If we want to be 95% confident that
the sample mean is
within 2 inches of the true population mean, what is the minimum sample
size that can be taken?
z0.101.282z0.051.645z0.0251.960z0.012.326z0.0052.576
Use the table above for the z-score, and be sure to round up to the nearest integer.
Week 8 Final Exam
,QUESTION 1
Of the following pairs of events, which pair has mutually exclusive events?
rolling a sum greater than 7 from two rolls of a standard die and rolling
a 4 for the first throw
drawing a 2 and drawing a 4 with replacement from a standard deck of
cards rolling a sum of 9 from two rolls of a standard die and rolling a 2 for
the first roll drawing a red card and then drawing a black card with
replacement from a standard
deck of cards
QUESTION 2
Hugo averages 41 words per minute on a typing test with a standard
deviation of 7.5 words per minute. Suppose Hugo's words per minute
on a typing test are normally distributed. Let X= the number of words
per minute on a typing test.
Then, X∼N(41,7.5).
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z-score when x=45 is . This z-
score tells you that x=45 is standard
deviations to the (right/left) of the mean, .
Correctly fill in the blanks in the statement
above. Select the correct answer below:
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is −0.533. This z-score tells you that x=45 is 0.533
standard deviations to the left of the mean, 41.
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is −0.381. This z-score tells you that x=45 is 0.381
standard deviations to the left of the mean, 41.
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is 0.381. This z-score tells you that x=45 is 0.381
standard deviations to the right of the mean, 41.
Suppose Hugo types 45 words per minute in a typing test on Wednesday.
The z- score when x=45 is 0.533. This z-score tells you that x=45 is 0.533
standard deviations to the right of the mean, 41.
,QUESTION 3
A fitness center claims that the mean amount of time that a person spends
33 minutes. Identify the null hypothesis, H0, and the
at the gym per visit is
alternative hypothesis, Ha, in terms of the parameter μ.
Select the correct answer below:
H0: μ≠33; Ha:
μ=33 H0: μ=33;
Ha: μ≠33 H0:
μ≥33; Ha: μ<33
H0: μ≤33; Ha:
μ>33
QUESTION 4
A recent study suggested that 81% of senior citizens take at least one
prescription medication. Amelia is a nurse at a large hospital who would
like to know whether the
percentage is the same for senior citizen patients who go to her hospital.
She randomly selects 59 senior citizens patients who were treated at the
hospital and finds
that 49 of them take at least one prescription medication. What are the null
and alternative hypotheses for this hypothesis test?
{H0:p=0.81Ha:p>0.81
{H0:p≠0.81Ha:p=0.81
{H0:p=0.81Ha:p<0.81
{H0:p=0.81Ha:p≠0.81
QUESTION 5
, A doctor notes her patient's temperature in degrees Fahrenheit every hour to make
sure the patient does not get a fever. What is the level of measurement of the data.
nomin
al
ordinal
interva
l ratio
QUESTION 6
Assume the null hypothesis, H0, is: Jacob earns enough money to afford a luxury
apartment. Find the Type I error in this scenario.
Jacob thinks he does not earn enough money to afford the luxury apartment
when, in fact, he does.
Jacob thinks he does not earn enough money to afford the luxury apartment
when, in fact, he does not.
Jacob thinks he earns enough money to afford the luxury apartment when, in
fact, he does
not.
Jacob thinks he earns enough money to afford the luxury apartment when, in
fact, he does.
QUESTION 7
The population standard deviation for the heights of dogs, in
inches, in a city is 3.7 inches. If we want to be 95% confident that
the sample mean is
within 2 inches of the true population mean, what is the minimum sample
size that can be taken?
z0.101.282z0.051.645z0.0251.960z0.012.326z0.0052.576
Use the table above for the z-score, and be sure to round up to the nearest integer.
