Standard Deviation and Cash Flow

Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.

State the null and alternative hypotheses.

A. H0:  = .79, H1:  > .79

B. H0: p = .79, H1: p ≠ .79

C. H0: p ≤ .79, H1: p > .79

D. H0: = .79, H1: > .79
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Question 2 of 10 1.0 Points
Consider the following scenario in answering questions 1 through 4. Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.

Compute the z or t value of the sample test statistic.
A. z = 0.69

B. t = 1.645

C. z = 1.96

D. z = 0.62
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Question 3 of 10 1.0 Points
Consider the following scenario in answering questions 1 through 4. Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.

What is your conclusion?

A. Do not reject H0. There is not enough evidence to support the claim that the proportion of students planning to go to college is greater than .79.
B. Reject H0. There is enough evidence to support the claim that the proportion of students planning to go to college is now greater than .79.
C. Cannot determine

D. More seniors are going to college
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Question 4 of 10 1.0 Points
Consider the following scenario in answering questions 1 through 4. Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.

What is the p-value associated with your test of hypothesis?
A. 0.7563

B. 0.6874

C. 0.4874

D. 0.2437
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Question 5 of 10 1.0 Points
Consider the following scenario in answering questions 5 through 7. In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.

State the null and alternative hypotheses.

A. H0: = 75, H1: ≠ 75

B. H0: 75, H1: > 75

C. H0: 75, H1: < 75

D. H0: = 75, H1: > 75
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Question 6 of 10 1.0 Points
Consider the following scenario in answering questions 5 through 7. In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.

Compute the z or t value of the sample test statistic.

A. z = 1.916

B. t = -1.916

C. t = 1.916

D. z = 1.645
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Question 7 of 10 1.0 Points
Consider the following scenario in answering questions 5 through 7. In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7. At the  = .05 level of significance, does the nutritionist have enough evidence to reject the writer’s claim?

A. No

B. Yes

C. Cannot Determine
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Question 8 of 10 1.0 Points
Consider the following in answering questions 8 through 10. A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?

State the null and alternative hypotheses.

A. H0:  < 1.2, H1:  ≠ 1.2

B. H0:  ≤ 1.2, H1:  > 1.2

C. H0:  ≠ 1.2, H1:  = 1.2

D. H0:  ≥ 1.2, H1:  ≠ 1.2
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Question 9 of 10 1.0 Points
Consider the following in answering questions 8 through 10. A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?Compute the value of the appropriate test statistic.

A. t = 27.50

B. z = 1.65

C. = 27.50

D. = 30.58
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Question 10 of 10 1.0 Points
Consider the following in answering questions 8 through 10. A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?

At the  = .01 level of significance, what is your conclusion?
A. Do not reject H0. At the = .01 level of significance there is not sufficient evidence to suggest that this technician’s true variance is greater than the target accuracy.
B. Reject H0. At the = .01 level of significance, there is enough evidence to support the claim that this technician’s variance is larger than the target accuracy. C. Cannot determine

D. Reject H0. At the = .01 level of significance, there is not enough evidence to support the claim that this technician’s true variance is larger than the target accuracy.