Section 8.2

Question #8

A 9-year-old girl did a science fair experiment in which she tested professional touch therapists to see if they could sense her energy field. She flipped a coin to select either her right hand or her left hand, and then she asked the therapists to identify the selected hand by placing their hand just under her hand without seeing it and without touching it. Among 256 trials, the touch therapists were correct 114 times. Use a 0.10 significance level to test the claim that touch therapists use a method equivalent to random guesses. Do the results suggest that touch therapists are effective?

Identify the null and alternative hypotheses for this test. Choose the correct answer below.

A. H₀: p=0.5

H₁: p0.5

B. H₀: p=0.5

H₁: p<0.5

C. H₀: p0.5

H₁: p=0.5

D. H₀: p=0.5

H₁: p>0.5

Identify the test statistic for this hypothesis test.

The test statistic for this hypothesis test is ________.

(Round to two decimal places as needed.)

Identify the P-value for this hypothesis test.

The P-value for this hypothesis test is _________.

(Round to three decimal places as needed.)

Identify the conclusion for this hypothesis test.

A. Failtoreject H₀. There isnot sufficient evidence to warrant rejection of the claim that touch therapists use a method equivalent to random guesses.

B. Failtoreject H₀. There is sufficient evidence to warrant rejection of the claim that touch therapists use a method equivalent to random guesses.

C. Reject H₀. There is sufficient evidence to warrant rejection of the claim that touch therapists use a method equivalent to random guesses.

D. Reject H₀. There isnot sufficient evidence to warrant rejection of the claim that touch therapists use a method equivalent to random guesses.

Do the results suggest that touch therapists are effective?

The results suggest that the touch therapists performed __________ (A. similarly to B. worse than C. better than ) random guesses, so they __________( A. do not appear, B. appear ) to be effective.

Question #9

In one study of smokers who tried to quit smoking with nicotine patch therapy, 39 were smoking one year after treatment and 31 were not smoking one year after the treatment. Use a 0.05 significance level to test the claim that among smokers who try to quit with nicotine patch therapy, the majority are smoking one year after the treatment. Do these results suggest that the nicotine patch therapy is not effective?

Identify the null and alternative hypotheses for this test. Choose the correct answer below.

A. H₀: p=0.5

H₁: p0.5

B. H₀: p=0.5

H₁: p<0.5

C. H₀: p>0.5

H₁: p=0.5

D. H₀: p=0.5

H₁: p>0.5

Identify the test statistic for this hypothesis test.

The test statistic for this hypothesis test is ________.

(Round to two decimal places as needed.)

Identify the P-value for this hypothesis test.

The P-value for this hypothesis test is _________.

(Round to three decimal places as needed.)

Identify the conclusion for this hypothesis test.

A. Failtoreject H₀. There sufficient evidence to warrant support of the claim that the majority are smoking one year after the treatment.

B. Failtoreject H₀. There insufficient evidence to warrant support of the claim that the majority are smoking one year after the treatment.

C. Reject H₀. There insufficient evidence to warrant support of the claim that the majority are smoking one year after the treatment.

D. Reject H₀. There sufficient evidence to warrant support of the claim that the majority are smoking one year after the treatment.

Do these results suggest that the nicotine patch therapy is not effective?

Since there is __________ ( A. insufficient, B. sufficient ) evidence to support the claim that the majority are smoking one year after the treatment, there is____________ ( A. sufficient B. insufficient) evidence to suggest that the nicotine patch is not effective.

Question #10

In a recent court case it was found that during a period of 11 years 856 people were selected for grand jury duty and 35% of them were from the same ethnicity. Among the people eligible for grand jury duty, 79.8% were of this ethnicity. Use a 0.01 significance level to test the claim that the selection process is biased against allowing this ethnicity to sit on the grand jury. Identify the null hypothesis, alternative hypothesis, test statistic, P-value, conclusion about the null hypothesis, and final conclusion that addresses the original claim. Use the P-value method and the normal distribution as an approximation to the binomial distribution.

Which of the following is the hypothesis test to be conducted?

A. H₀:p=0.798

H₁:p>0.798

B. H₀:p>0.798

H₁:p=0.798

C. H₀:p<0.798

H₁:p=0.798

D. H₀:p=0.798

H₁:p<0.798

E. H₀:p0.798

H₁:p=0.798

F. H₀:p=0.798

H₁:p0.798

What is the test statistic?

z= _________

(Round to two decimal places as needed.)

What is the P-value?

P-value= __________

(Round to four decimal places as needed.)

What is the conclusion on the null hypothesis?

A. Reject the null hypothesis because the P-value is lessthanorequalto the significance level, .

B. Failtoreject the null hypothesis because the P-value is greaterthan the significance level, .

C. Reject the null hypothesis because the P-value is greaterthan the significance level, .

D. Failtoreject the null hypothesis because the P-value is lessthanorequalto the significance level, .

Does the jury selection system appear to be fair?

A. There isnot sufficient evidence to support the claim that the selection process is biased against allowing this ethnicity to sit on the grand jury. The jury selection process appears to be unfair.

B. There isnot sufficient evidence to warrant rejection of the claim that the selection process is biased against allowing this ethnicity to sit on the grand jury. The jury selection process appears to be fair.

C. There is sufficient evidence to warrant rejection of the claim that the selection process is biased against allowing this ethnicity to sit on the grand jury. The jury selection process appears to be fair.

D. There is sufficient evidence to support the claim that the selection process is biased against allowing this ethnicity to sit on the grand jury. The jury selection process appears to be unfair.

Section 8.3

Question #1

Twenty-four different video games showing druguse were observed. The duration times of druguse (in seconds) were recorded. When using this sample for a t test of the claim that the population mean is greater than 82 sec, what does df denote, and what is its value?

What does df denote?

A. The number of degrees of freedom

B. The sample size

C. The sample standard deviation

D. The test statistic

The value of df is ________.

(Type an integer or a decimal. Do not round.)

Question #2

Use technology to find the P-value for the hypothesis test described below.

The claim is that for a smartphone carrier's data speeds at airports, the mean is

=11.00 Mbps. The sample size is n=21 and the test statistic is t= 1.335.

P-value= __________ (Round to three decimal places as needed.)

Question #3

Use technology to find the P-value for the hypothesis test described below.

The claim is that for 12 AM body temperatures, the mean is <98.6F.

The sample size is n=9 and the test statistic is t=2.279.

P-value= __________ (Round to three decimal places as needed.)