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Use the traditional method to test the given hypothesis. Assume that the population is normally distributed and that the sample has been randomly selected. For randomly selected adults, IQ scores are normally distributed with a standard deviation of 15. The scores of 14 randomly selected college students are listed below. Use a 0.10 significance level to test the claim that the standard deviation of IQ scores of college students is less than 15. Round the sample standard deviation to three decimal places. 115128107109116124135127115104118126129133\begin{array} { l l l l l l l } 115 & 128 & 107 & 109 & 116 & 124 & 135 \\127 & 115 & 104 & 118 & 126 & 129 & 133\end{array}

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Test statistic: blured image. Critical val...

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Formulate the indicated conclusion in nontechnical terms. Be sure to address the original claim. The owner of a football team claims that the average attendance at games is over 523, and he is Therefore justified in moving the team to a city with a larger stadium. Assuming that a Hypothesis test of the claim has been conducted and that the conclusion is failure to reject the Null hypothesis, state the conclusion in nontechnical terms.


A) There is sufficient evidence to support the claim that the mean attendance is less than 523.
B) There is not sufficient evidence to support the claim that the mean attendance is less than 523.
C) There is sufficient evidence to support the claim that the mean attendance is greater than 523.
D) There is not sufficient evidence to support the claim that the mean attendance is greater than 523.

E) All of the above
F) A) and D)

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Find the value of the test statistic zz using z=p^ppqnz = \frac { \hat { p } - p } { \sqrt { \frac { p q } { n } } } . The claim is that the proportion of drowning deaths of children attributable to beaches is more than 0.250.25 , and the sample statistics include n=696\mathrm { n } = 696 drowning deaths of children with 30%30 \% of them attributable to beaches.


A) 2.882.88
B) 3.053.05
C) 3.05- 3.05
D) 2.88- 2.88 .

E) B) and D)
F) A) and D)

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A hypothesis test is performed to test the claim that a population proportion is greater than 0.7. Find the probability of a type II error, β\beta , given that the true value of the population proportion Is 0.72. The sample size is 50 and the significance level is 0.05.


A) 0.4129
B) 0.5754
C) 0.7123
D) 0.9706

E) A) and B)
F) A) and C)

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Find the critical value or values of χ2\chi ^ { 2 } based on the given information. H1:σ<0.629n=19α=0.025\begin{array} { l } H _ { 1 } : \sigma < 0.629 \\n = 19 \\\alpha = 0.025\end{array}


A) 8.2318.231
B) 31.52631.526
C) 7.0157.015
D) 8.9078.907

E) A) and B)
F) All of the above

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Solve the problem. A hypothesis test is performed to test the claim that a population proportion is greater than 0.7. Find the probability of a type II error, BB , given that the true value of the Population proportion is 0.72. The sample size is 50 and the significance level is 0.05.


A) 0.4129
B) 0.7123
C) 0.5754
D) 0.9706

E) A) and B)
F) A) and D)

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Use the given information to find the PP -value. Also, use a 0.050.05 significance level and state the conclusion about the null hypothesis (reject the null hypothesis or fail to reject the null hypothesis) . With H1:p0.377H _ { 1 } : p \neq 0.377 , the test statistic is z=3.06z = 3.06 .


A) 0.00110.0011 ; reject the null hypothesis
B) 0.00220.0022 ; fail to reject the null hypothesis
C) 0.00220.0022 ; reject the null hypothesis
D) 0.00110.0011 ; fail to reject the null hypothesis

E) B) and C)
F) A) and C)

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Solve the problem. For large numbers of degrees of freedom, the critical χ2\chi ^ { 2 } values can be approximated as follows: χ2=12(z+2k1) 2\chi ^ { 2 } = \frac { 1 } { 2 } ( z + \sqrt { 2 k - 1 } ) ^ { 2 } , where k\mathrm { k } is the number of degrees of freedom and zz is the critical value. To find the lower critical value, the negative zz -value is used, to find the upper critical value, the positive zz -value is used. Use this approximation to estimate the critical value of χ2\chi ^ { 2 } in a two-tailed hypothesis test with n=104n = 104 and α=0.10\alpha = 0.10 .


A) χ284.992\chi ^ { 2 } \approx 84.992 and χ2121.646\chi ^ { 2 } \approx 121.646
B) χ281.186\chi ^ { 2 } \approx 81.186 and χ2128.520\chi ^ { 2 } \approx 128.520
C) χ280.300\chi ^ { 2 } \approx 80.300 and χ2127.406\chi ^ { 2 } \approx 127.406
D) χ285.903\chi ^ { 2 } \approx 85.903 and χ2122.735\chi ^ { 2 } \approx 122.735

E) B) and C)
F) None of the above

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A chi-square hypothesis test is going to be conducted about a population standard deviation. Select the statement that is not true about the Chi-square test


A) The sample must be a simple random sample.
B) The population does not have to be a normally distributed population.
C) The alternative hypothesis must contain <,>< , > , or \neq .
D) The sample size must be known.

E) C) and D)
F) None of the above

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Find the value of the test statistic zz using z=p^ppqnz = \frac { \hat { p } - p } { \sqrt { \frac { p q } { n } } } . A claim is made that the proportion of children who play sports is less than 0.50.5 , and the sample statistics include n=1320n = 1320 subjects with 30%30 \% saying that they play a sport.


A) 14.5314.53
B) 29.6629.66
C) 29.66- 29.66
D) 14.53- 14.53

E) None of the above
F) B) and D)

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Suppose we want to test the claim that less than 1/21 / 2 of Americans are in favor of raising the voting age to 21. Is the hypothesis test left-tailed, right-tailed, or two-tailed?


A) Left-tailed
B) Right-tailed
C) Two-tailed
114

D) B) and C)
E) A) and C)

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The p-value is the probability of getting a test statistic at least as extreme as the one representing the sample data, assuming that ______________________________.


A) the null hypothesis is true
B) the null hypothesis is false
C) the alternative hypothesis is true
D) the alternative hypothesis is false

E) A) and D)
F) A) and C)

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A simple random sample of the running time of movies of 70 international movies resulted in a sample mean length of 112 minutes and a sample standard deviation of 7 minutes. Test the claim that international movies have a mean running time of more than 110 minutes at the 5% level of significance. Assume that the lengths of movies are normally distributed.

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. Reject the null hypothesis. ...

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Express the original claim in symbolic form. Claim: 20% of adults smoke


A) p0.2p \neq 0.2
B) p=0.2p = 0.2
C) μ0.2\mu \neq 0.2
D) μ=0.2\mu = 0.2

E) All of the above
F) B) and D)

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Express the null hypothesis and the alternative hypothesis in symbolic form. Use the correct symbol (μ,p,σ) ( \mu , p , \sigma ) for the indicated parameter. A psychologist claims that more than 5.85.8 percen of the population suffers from professional problems due to extreme shyness. Use pp , the true percentage of the population that suffers from extreme shyness.


A) H0:p=5.8%H _ { 0 } : p = 5.8 \%
H1:p<5.8%H _ { 1 } : p < 5.8 \%

B) H0:p=5.8%H _ { 0 } : p = 5.8 \%
H1:p5.8%H _ { 1 } : p \leq 5.8 \%

C) H0:p=5.8%H _ { 0 } : p = 5.8 \%
H1:p>5.8%H _ { 1 } : p > 5.8 \%

D) H0:p<5.8%H _ { 0 } : p < 5.8 \%
H1:p5.8%H _ { 1 } : p \geq 5.8 \%

E) B) and D)
F) C) and D)

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The ________________ is the probability of getting a test statistic at least as extreme as the one representing the sample data, assuming that the null hypothesis is true.


A) P-value
B) sample proportion
C) critical value
D) level of significance

E) C) and D)
F) B) and D)

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An oil change shop claims that they will change your oil in under 15 minutes. To test this claim, a consumer advocacy group takes a simple random sample of 10 customers and records the number of minutes it took to complete oil changes for these customers. Assume that oil change times are normally distributed.  Minutes for Oil Change 8271214112584315\begin{array} { | c | } \hline \text { Minutes for Oil Change } \\\hline 8 \\\hline 2 \\\hline 7 \\\hline 12 \\\hline 14 \\\hline 11 \\\hline 25 \\\hline 8 \\\hline 43 \\\hline 15 \\\hline\end{array} Conduct a hypothesis test for the oil shop's claim about oil change times at the 5% level of significance. 118

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\[\begin{array} { l }
H _ { 0 } : \mu =...

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Suppose we want to test the claim that the majority of adults are in favor of raising the voting age to 21. Is the hypothesis test left-tailed, right-tailed, or two-tailed?


A) Left-tailed
B) Right-tailed
C) Two-tailed

D) All of the above
E) A) and B)

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Formulate the indicated conclusion in nontechnical terms. Be sure to address the original claim. Carter Motor Company claims that its new sedan, the Libra, will average better than 32 miles Per gallon in the city. Assuming that a hypothesis test of the claim has been conducted and That the conclusion is to reject the null hypothesis, state the conclusion in nontechnical terms.


A) There is not sufficient evidence to support the claim that the mean is greater than 32 miles per gallon.
B) There is not sufficient evidence to support the claim that the mean is less than 32 miles per gallon.
C) There is sufficient evidence to support the claim that the mean is less than 32 miles per gallon.
D) There is sufficient evidence to support the claim that the mean is greater than 32 miles per gallon.

E) None of the above
F) A) and C)

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Express the null hypothesis and the alternative hypothesis in symbolic form. Use the correct symbol (μ,p,σ) ( \mu , p , \sigma ) for the indicated parameter. An entomologist writes an article in a scienti journal which claims that fewer than 16 in ten thousand male fireflies are unable to produce light due to a genetic mutation. Use the parameter p\mathrm { p } , the true proportion of fireflies unable produce light.


A) H0:p=0.0016H _ { 0 } : p = 0.0016
H1:p<0.0016H _ { 1 } : p < 0.0016

B) H0:p<0.0016H _ { 0 } : p < 0.0016
H1:p0.0016H _ { 1 } : p \geq 0.0016

C) H0:p=0.0016H _ { 0 } : p = 0.0016
H1:p>0.0016H _ { 1 } : p > 0.0016

D) H0:p>0.0016H _ { 0 } : p > 0.0016
H1:p0.0016H _ { 1 } : p \leq 0.0016

E) All of the above
F) None of the above

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