Question 1

A power curve is a graphic that plots

Accepted Answer

A)  the power of the test against values of the population mean that make $\mathrm { H } _ { 0 }$ false. 
B)  the power of the test against values of the population mean that make $\mathrm { H } _ { 0 }$ true. 
C)  the power of the test against values of the hypothesized mean that make $\mathrm { H } _ { 0 }$ false. 
D)  the power of the test against values of the hypothesized mean that make $\mathrm { H } _ { 0 }$ true. 
A)  the power of the test against values of the population mean that make $\mathrm { H } _ { 0 }$ false. 
B)  the power of the test against values of the population mean that make $\mathrm { H } _ { 0 }$ true. 
C)  the power of the test against values of the hypothesized mean that make $\mathrm { H } _ { 0 }$ false. 
D)  the power of the test against values of the hypothesized mean that make $\mathrm { H } _ { 0 }$ true.

Question 2

Determine the critical value for a left-tailed test of a population mean at the α = 0.005 level of significancebased on a sample size of n = 30.

Accepted Answer

A)  -2.756 
B)  -1.699 
C)  2.756 
D)  2.750 
A)  -2.756 
B)  -1.699 
C)  2.756 
D)  2.750

Question 3

The mean monthly gasoline bill for one household is greater than $150. If a hupothesis test is performed, how should you interpret a dicision that fails to reject the null hypothesis?

Accepted Answer

A)  There is  sufficient evidence to support the claim $$\mu > \$ 150$$ 
B)  There is sufficient evidence to reject the claim $$\mu > \$ 150$$ 
C)  There is not sufficient evidence to reject the claim $$\mu > \$ 150$$ 
D)  There is not sufficient evidence to support  the claim $$\mu > \$ 150$$ 
A)  There is  sufficient evidence to support the claim $$\mu > \$ 150$$ 
B)  There is sufficient evidence to reject the claim $$\mu > \$ 150$$ 
C)  There is not sufficient evidence to reject the claim $$\mu > \$ 150$$ 
D)  There is not sufficient evidence to support  the claim $$\mu > \$ 150$$

Question 4

Test the claim about the population proportion p ≥ 0.700 given  n=50  and  $\hat { \mathrm { p } } = 0.612 . \text { Use } \alpha = 0.10$

Accepted Answer

critical value @#LAT-DLM& standardized t

Question 5

Increasing numbers of businesses are offering child-care benefits for their workers. However, one union claimsthat more than 85% of firms in the manufacturing sector still do not offer any child-care benefits to theirworkers. A random sample of 430 manufacturing firms is selected, and only 32 of them offer child-carebenefits. Specify the rejection region that the union will use when testing at α = 0.10.

Accepted Answer

To determine if more than 85%

Question 6

Compute the standardized test statistic, $\chi ^ { 2 }$ to test the claim $\sigma ^ { 2 } \geq 7.2 \text { if } n = 15 , \mathrm {~s} ^ { 2 } = 6 , \text { and } \alpha = 0.05$

Accepted Answer

A)   11.667 
B)   8.713 
C)   12.823 
D)   23.891 
A)   11.667 
B)   8.713 
C)   12.823 
D)   23.891

Question 7

Find the standardized test statistic t for a sample with $$\mathrm { n } = 20 , \overline { \mathrm { x } } = 13.3 , \mathrm {~s} = 2.0 , \text { and } \alpha = 0.05 \text { if } \mathrm { H } _ { 1 } : \mu < 13.7$$ Round your answer to three decimal places.

Accepted Answer

A)  -0.894 
B)  -0.872 
C)  -1.265 
D)  -1.233 
A)  -0.894 
B)  -0.872 
C)  -1.265 
D)  -1.233

Question 8

The weekly salaries (in dollars) of randomly selected employees of a company are summarized in the boxplotbelow. Based on the boxplot, is a large sample necessary to conduct a hypothesis test about the mean salary? Ifso, why?

Accepted Answer

A)  Yes; data do not appear to be normally distributed but skewed right. 
B)  Yes; data do not appear to be normally distributed but skewed left. 
C)  No; data appear to be normally distributed. 
D)  Yes; data contain outliers. 
A)  Yes; data do not appear to be normally distributed but skewed right. 
B)  Yes; data do not appear to be normally distributed but skewed left. 
C)  No; data appear to be normally distributed. 
D)  Yes; data contain outliers.

Question 9

Fifty percent of registered voters in a congressional district are registered Democrats. The Republican candidatetakes a poll to assess his chances in a two-candidate race. He polls 1200 potential voters and finds that 621 planto vote for the Democratic candidate. Does the Republican candidate have a chance to win? Use α = 0.05.

Accepted Answer

critical value @#LAT-DLM&; standardized

Question 10

Find the standardized test statistic t for a sample with $$\mathrm { n } = 12 , \overline { \mathrm { x } } = 15.7 , \mathrm {~s} = 2.1 , \text { and } \alpha = 0.01 \text { if } \mathrm { H } _ { 1 } : \mu \neq 16.2$$ Round your answer to three decimal places.

Accepted Answer

A)  -0.825 
B)  -0.008 
C)  -0.037 
D)  -0.381 
A)  -0.825 
B)  -0.008 
C)  -0.037 
D)  -0.381

Question 11

Test the claim that   Assume that the population is normally distributed.

Accepted Answer

critical value @#LAT-DLM& standardized t

Question 12

Find the critical value for a left-tailed test with α = 0.025.

Accepted Answer

A)  -1.96 
B)  -2.24 
C)  -1.645 
D)  -2.575 
A)  -1.96 
B)  -2.24 
C)  -1.645 
D)  -2.575

Question 13

Test the claim that $\sigma ^ { 2 } > 17.1 \text { if } n = 18 , s ^ { 2 } = 24.3 , \text { and } \alpha = 0.01$ Assume that the population is normally distributed.

Accepted Answer

critical value  @#LAT-DLM&=33.409 ;  sta

Question 14

An event is considered unusual if the probability of observing the event is

Accepted Answer

A)  less than 0.05 
B)  less than 0.025 
C)  less than 0.10 
D)  greater than 0.95 
A)  less than 0.05 
B)  less than 0.025 
C)  less than 0.10 
D)  greater than 0.95

Question 15

A candidate for state representative of a certain state claims to be favored by at least half of the voters. If ahypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

A)  There is sufficient evidence to reject the claim $\mathrm { p } \geq 0.5$. 
B)  There is not sufficient evidence to reject the claim $p \geq 0.5$. 
C)  There is sufficient evidence to support the claim $p \geq 0.5$. 
D)  There is not sufficient evidence to support the claim $p \geq 0.5$. 
A)  There is sufficient evidence to reject the claim $\mathrm { p } \geq 0.5$. 
B)  There is not sufficient evidence to reject the claim $p \geq 0.5$. 
C)  There is sufficient evidence to support the claim $p \geq 0.5$. 
D)  There is not sufficient evidence to support the claim $p \geq 0.5$.

Question 16

Use a t-test to test the claim μ > 34 at α = 0.005 given the sample statistics $\mathrm { n } = 25 , \mathrm { x } = 35 , \text { and } \mathrm { s } = 3$Round the test statistic to the nearest thousandth.

Accepted Answer

@#LAT-DLM&  standardized test statistic

Question 17

A survey claims that 9 out of 10 doctors (i.e., 90%) recommend brand Z for their patients who have children. Totest this claim against the alternative that the actual proportion of doctors who recommend brand Z is less than90%, a random sample of 100 doctors results in 83 who indicate that they recommend brand Z. The test statisticin this problem is approximately (round to the nearest hundredth):

Accepted Answer

A)  -2.33 
B)  2.33 
C)  -1.83 
D)  -1.99 
A)  -2.33 
B)  2.33 
C)  -1.83 
D)  -1.99

Question 18

A recent study claimed that at least  15 %  of junior high students are overweight. In a sample of 160 students, 18 were found to be overweight. At α=0.05 , test the claim.

Accepted Answer

critical value @#LAT-DLM& standardized t

Question 19

A manufacturer claims that the mean lifetime of its lithium batteries is 1400 hours. A homeowner selects 25 ofthese batteries and finds the mean lifetime to be 1380 hours with a standard deviation of 80 hours. Test themanufacturerʹs claim. Use α = 0.05. Round the test statistic to the nearest thousandth.

Accepted Answer

critical value @#LAT-DLM&; standardized

Question 20

The mean monthly gasoline bill for one household is greater than $160. If a hupothesis test is performed, how should you interpret a dicision that fails to reject the null hypothesis?

Accepted Answer

A)  There is not sufficient evidence to support the claim $$\mu > \$ 160$$ 
B)  There is sufficient evidence to reject the claim $$\mu > \$ 160$$ 
C)  There is not sufficient evidence to reject the claim $$\mu > \$ 160$$ 
D)  There is sufficient evidence to support  the claim $$\mu > \$ 160$$ 
A)  There is not sufficient evidence to support the claim $$\mu > \$ 160$$ 
B)  There is sufficient evidence to reject the claim $$\mu > \$ 160$$ 
C)  There is not sufficient evidence to reject the claim $$\mu > \$ 160$$ 
D)  There is sufficient evidence to support  the claim $$\mu > \$ 160$$

A power curve is a graphic that plots

Determine the critical value for a left-tailed test of a population mean at the α = 0.005 level of significancebased on a sample size of n = 30.

The mean monthly gasoline bill for one household is greater than $150. If a hupothesis test is performed, how should you interpret a dicision that fails to reject the null hypothesis?

Test the claim about the population proportion p ≥ 0.700 given n=50 and $\hat { \mathrm { p } } = 0.612 . \text { Use } \alpha = 0.10$

Compute the standardized test statistic, $\chi ^ { 2 }$ to test the claim $\sigma ^ { 2 } \geq 7.2 \text { if } n = 15 , \mathrm {~s} ^ { 2 } = 6 , \text { and } \alpha = 0.05$

Find the standardized test statistic t for a sample with $\mathrm { n } = 20 , \overline { \mathrm { x } } = 13.3 , \mathrm {~s} = 2.0 , \text { and } \alpha = 0.05 \text { if } \mathrm { H } _ { 1 } : \mu < 13.7$ Round your answer to three decimal places.

The weekly salaries (in dollars) of randomly selected employees of a company are summarized in the boxplotbelow. Based on the boxplot, is a large sample necessary to conduct a hypothesis test about the mean salary? Ifso, why?

Find the standardized test statistic t for a sample with $\mathrm { n } = 12 , \overline { \mathrm { x } } = 15.7 , \mathrm {~s} = 2.1 , \text { and } \alpha = 0.01 \text { if } \mathrm { H } _ { 1 } : \mu \neq 16.2$ Round your answer to three decimal places.

Test the claim that Assume that the population is normally distributed.

Find the critical value for a left-tailed test with α = 0.025.

Test the claim that $\sigma ^ { 2 } > 17.1 \text { if } n = 18 , s ^ { 2 } = 24.3 , \text { and } \alpha = 0.01$ Assume that the population is normally distributed.

An event is considered unusual if the probability of observing the event is

A candidate for state representative of a certain state claims to be favored by at least half of the voters. If ahypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Use a t-test to test the claim μ > 34 at α = 0.005 given the sample statistics $\mathrm { n } = 25 , \mathrm { x } = 35 , \text { and } \mathrm { s } = 3$ Round the test statistic to the nearest thousandth.

A recent study claimed that at least 15 % of junior high students are overweight. In a sample of 160 students, 18 were found to be overweight. At α=0.05 , test the claim.

The mean monthly gasoline bill for one household is greater than $160. If a hupothesis test is performed, how should you interpret a dicision that fails to reject the null hypothesis?

Data Collection

Organizing and Summarizing Data

Numerically Summarizing Data

Describing the Relation Between Two Variables

Probability

Discrete Probability Distributions

The Normal Probability Distribution

Sampling Distributions

Estimating the Value of a Parameter

Inferences on Two Samples

Inference on Categorical Data

Comparing Three or More Means

Filters

Exam 10: Hypothesis Tests Regarding a Parameter

A power curve is a graphic that plots

Determine the critical value for a left-tailed test of a population mean at the α = 0.005 level of significancebased on a sample size of n = 30.

The mean monthly gasoline bill for one household is greater than $150. If a hupothesis test is performed, how should you interpret a dicision that fails to reject the null hypothesis?

Test the claim about the population proportion p ≥ 0.700 given n=50 and p^=0.612. Use α=0.10\hat { \mathrm { p } } = 0.612 . \text { Use } \alpha = 0.10p^​=0.612. Use α=0.10

Compute the standardized test statistic, χ2\chi ^ { 2 }χ2 to test the claim σ2≥7.2 if n=15, s2=6, and α=0.05\sigma ^ { 2 } \geq 7.2 \text { if } n = 15 , \mathrm {~s} ^ { 2 } = 6 , \text { and } \alpha = 0.05σ2≥7.2 if n=15, s2=6, and α=0.05

The weekly salaries (in dollars) of randomly selected employees of a company are summarized in the boxplotbelow. Based on the boxplot, is a large sample necessary to conduct a hypothesis test about the mean salary? Ifso, why?

Test the claim that Assume that the population is normally distributed.

Find the critical value for a left-tailed test with α = 0.025.

Test the claim that σ2>17.1 if n=18,s2=24.3, and α=0.01\sigma ^ { 2 } > 17.1 \text { if } n = 18 , s ^ { 2 } = 24.3 , \text { and } \alpha = 0.01σ2>17.1 if n=18,s2=24.3, and α=0.01 Assume that the population is normally distributed.

An event is considered unusual if the probability of observing the event is

A candidate for state representative of a certain state claims to be favored by at least half of the voters. If ahypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Use a t-test to test the claim μ > 34 at α = 0.005 given the sample statistics n=25,x=35, and s=3\mathrm { n } = 25 , \mathrm { x } = 35 , \text { and } \mathrm { s } = 3n=25,x=35, and s=3 Round the test statistic to the nearest thousandth.

A recent study claimed that at least 15 % of junior high students are overweight. In a sample of 160 students, 18 were found to be overweight. At α=0.05 , test the claim.

The mean monthly gasoline bill for one household is greater than $160. If a hupothesis test is performed, how should you interpret a dicision that fails to reject the null hypothesis?

Data Collection

Organizing and Summarizing Data

Numerically Summarizing Data

Describing the Relation Between Two Variables

Probability

Discrete Probability Distributions

The Normal Probability Distribution

Sampling Distributions

Estimating the Value of a Parameter

Inferences on Two Samples

Inference on Categorical Data

Comparing Three or More Means

Filters

Test the claim about the population proportion p ≥ 0.700 given n=50 and $\hat { \mathrm { p } } = 0.612 . \text { Use } \alpha = 0.10$

Compute the standardized test statistic, $\chi ^ { 2 }$ to test the claim $\sigma ^ { 2 } \geq 7.2 \text { if } n = 15 , \mathrm {~s} ^ { 2 } = 6 , \text { and } \alpha = 0.05$

Test the claim that $\sigma ^ { 2 } > 17.1 \text { if } n = 18 , s ^ { 2 } = 24.3 , \text { and } \alpha = 0.01$ Assume that the population is normally distributed.

Use a t-test to test the claim μ > 34 at α = 0.005 given the sample statistics $\mathrm { n } = 25 , \mathrm { x } = 35 , \text { and } \mathrm { s } = 3$ Round the test statistic to the nearest thousandth.