Quiz Submissions - Final Review
Question 1 point
Determine type and strength of the association.
Data shown on the following scatter-plot indicate a correlation of 0.96 between the average
flow rate and pressure.
Describe the association.
Question options:
Strong positive correlation
Weak negative correlation
No evidence of a correlation
Strong negative correlation
Weak positive correlation
Question 1/1
2 point
Determine the margin of error.
An article in an educational journal discussing a non-conventional high school reading program
reports a 95% confidence interval of (520 , 560) for the average score on the reading portion of
the SAT. The study was based on a random sample of 20 students and it was assumed that SAT
scores would be approximately normally distributed.
Determine the margin of error associated with this confidence interval.
Question options:
15
40
10
5
20
Question 1/1
3 point
, Conduct the appropriate hypothesis test and compute the test statistic.
A company that produces fishing line undergoes random testing to see if their fishing line holds
up to the advertised specifications. Currently they are producing 30-pound test line and 20
randomly selected pieces are selected to test the strength. The 20 pieces broke with an average
force of 29.1 pounds and a sample standard deviation of 2 pounds. Assuming that the strength
of the fishing line is normally distributed, perform the appropriate hypothesis test at a 0.05
significance level in order to determine whether there is sufficient sample evidence to conclude
the fishing line breaks with an average force of less than 30 pounds.
Question options:
Cannot be determined
No, because the test statistic is -2.01
Yes, because the test statistic is -2.01
Yes, because the test statistic is -2.52
No, because the test statistic is -2.52
Question 1/1
4 point
Conduct the appropriate hypothesis test and compute the test statistic.
A hypnotist believes that his program can help more the 50% of patients quit smoking.
To test this claim, a random sample of 100 patients were monitored for one-year and 57 had
quite smoking.
Compute the test statistic.
Question options:
0.08
1.40
0.57
0.50
1.73
Question 1/1
5 point
Interpret the association.
There is a strong positive correlation between a person’s annual income and outstanding debt.
Therefore, it can be concluded that:
Question options:
those with higher annual incomes tend to have less outstanding debt.
those with large enough incomes do not have any outstanding debt.
those with higher annual incomes tend to have more outstanding debt.
a lack of income will cause a person to go into debt.
nothing can be concluded from a positive correlation.
Question 1/1
, 6 point
Select the most appropriate response.
In hypothesis testing, a Type I error occurs when:
Question options:
the null hypothesis is not rejected when the alternative hypothesis is true.
the null hypothesis is rejected when the null hypothesis is true.
the null hypothesis is not rejected when the null hypothesis is true
the null hypothesis is rejected when the alternative hypothesis is true.
Question 1/1
7 point
For the given significance test, explain the meaning of a Type II error.
A certain academic program boasts that 87% of their graduates find full-time employment in
their field within the first year of graduation. The academic director is concerned that market
factors may have adversely affected the full-time placement rate and decides to perform a
Hypothesis Test to see if her concern is warranted.
H0 : p=0.87{"version":"1.1","math":"<math
xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>H</mi><mn>0</mn></msub><
mo> </mo><mo>:</mo><mo> </mo><mi>p</mi><mo>=</mo><mn>0</mn><mo
>.</mo><mn>87</mn></math>"}
H1: p<0.87{"version":"1.1","math":"<math
xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>H</mi><mn>1</mn></msub><
mo>:</mo><mo> </mo><mi>p</mi><mo><</mo><mn>0</mn><mo>.</mo><mn>87<
/mn></math>"}
In this situation, explain the meaning of a Type II error.
Question options:
Not concluding that the proportion is equal to 0.72 when it actually is.
The academic director concludes that the placement rate has decreased as a result of
market factors.
The academic director concludes that the placement rate has decreased when it
actually has not.
The academic director does not conclude that the placement rate has decreased when
it actually has.
The academic director does not conclude that the placement rate has decreased when
it has actually increased.
Question 1/1
8 point
Construct the requested confidence interval.
A meteorologist was interested in the average speed of a thunderstorm in his area. He sampled
13 thunderstorms and found that the average speed at which they traveled across the area was
15 miles per hour with a sample standard deviation of 1.7 miles per hour.
Question 1 point
Determine type and strength of the association.
Data shown on the following scatter-plot indicate a correlation of 0.96 between the average
flow rate and pressure.
Describe the association.
Question options:
Strong positive correlation
Weak negative correlation
No evidence of a correlation
Strong negative correlation
Weak positive correlation
Question 1/1
2 point
Determine the margin of error.
An article in an educational journal discussing a non-conventional high school reading program
reports a 95% confidence interval of (520 , 560) for the average score on the reading portion of
the SAT. The study was based on a random sample of 20 students and it was assumed that SAT
scores would be approximately normally distributed.
Determine the margin of error associated with this confidence interval.
Question options:
15
40
10
5
20
Question 1/1
3 point
, Conduct the appropriate hypothesis test and compute the test statistic.
A company that produces fishing line undergoes random testing to see if their fishing line holds
up to the advertised specifications. Currently they are producing 30-pound test line and 20
randomly selected pieces are selected to test the strength. The 20 pieces broke with an average
force of 29.1 pounds and a sample standard deviation of 2 pounds. Assuming that the strength
of the fishing line is normally distributed, perform the appropriate hypothesis test at a 0.05
significance level in order to determine whether there is sufficient sample evidence to conclude
the fishing line breaks with an average force of less than 30 pounds.
Question options:
Cannot be determined
No, because the test statistic is -2.01
Yes, because the test statistic is -2.01
Yes, because the test statistic is -2.52
No, because the test statistic is -2.52
Question 1/1
4 point
Conduct the appropriate hypothesis test and compute the test statistic.
A hypnotist believes that his program can help more the 50% of patients quit smoking.
To test this claim, a random sample of 100 patients were monitored for one-year and 57 had
quite smoking.
Compute the test statistic.
Question options:
0.08
1.40
0.57
0.50
1.73
Question 1/1
5 point
Interpret the association.
There is a strong positive correlation between a person’s annual income and outstanding debt.
Therefore, it can be concluded that:
Question options:
those with higher annual incomes tend to have less outstanding debt.
those with large enough incomes do not have any outstanding debt.
those with higher annual incomes tend to have more outstanding debt.
a lack of income will cause a person to go into debt.
nothing can be concluded from a positive correlation.
Question 1/1
, 6 point
Select the most appropriate response.
In hypothesis testing, a Type I error occurs when:
Question options:
the null hypothesis is not rejected when the alternative hypothesis is true.
the null hypothesis is rejected when the null hypothesis is true.
the null hypothesis is not rejected when the null hypothesis is true
the null hypothesis is rejected when the alternative hypothesis is true.
Question 1/1
7 point
For the given significance test, explain the meaning of a Type II error.
A certain academic program boasts that 87% of their graduates find full-time employment in
their field within the first year of graduation. The academic director is concerned that market
factors may have adversely affected the full-time placement rate and decides to perform a
Hypothesis Test to see if her concern is warranted.
H0 : p=0.87{"version":"1.1","math":"<math
xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>H</mi><mn>0</mn></msub><
mo> </mo><mo>:</mo><mo> </mo><mi>p</mi><mo>=</mo><mn>0</mn><mo
>.</mo><mn>87</mn></math>"}
H1: p<0.87{"version":"1.1","math":"<math
xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>H</mi><mn>1</mn></msub><
mo>:</mo><mo> </mo><mi>p</mi><mo><</mo><mn>0</mn><mo>.</mo><mn>87<
/mn></math>"}
In this situation, explain the meaning of a Type II error.
Question options:
Not concluding that the proportion is equal to 0.72 when it actually is.
The academic director concludes that the placement rate has decreased as a result of
market factors.
The academic director concludes that the placement rate has decreased when it
actually has not.
The academic director does not conclude that the placement rate has decreased when
it actually has.
The academic director does not conclude that the placement rate has decreased when
it has actually increased.
Question 1/1
8 point
Construct the requested confidence interval.
A meteorologist was interested in the average speed of a thunderstorm in his area. He sampled
13 thunderstorms and found that the average speed at which they traveled across the area was
15 miles per hour with a sample standard deviation of 1.7 miles per hour.
