1) Choose the one alternative that best completes the statement or answers the question.

To construct a confidence interval for the difference of two population proportions the samples must be

independently obtained random samples, both must consist of less than 5% of the population, and

A) both np1 (1- p1) 10 and np2(1- p2) 10 must be true.

B) np1(1- p1) + np2 (1- p2) 20.

C) np1(1- p1) x np2 (1- p2) 100.

D) only one of np1(1- p1) 10 or np2 (1- p2) 10 must be true.

2) The numbers of successes and the sample sizes are given for independent simple random samples from two

populations. Decide whether using the two-proportions z-procedures is appropriate.

Data:

x1= 58,

n1= 60

x2 = 45,

n2= 50

A) Appropriate

B) Not appropriate

C) Not enough information

D) Unable to know p1and p2

3) A researcher believes that the proportion of women who exercise with a friend is greater than the proportion of men.

He takes a random sample from each population and records the response to the question, "Have you exercised with a

friend at least once in the last seven days?" The null hypothesis is

H0: pwomen= pmen. Choose the correct alternative hypothesis.

A) H1: p = 0

B) H1: pwomen pmen

C) H1: pwomen> pmen

D)H1: pwomen< pmen

4) A researcher conducts a hypothesis test on a population proportion.

Her null and alternative hypothesis are

H0: p = 0.4 and

H1: p 0.4 .

The test statistic and p-value for the test are z = 3.01 and p-value = 0.0013. For a significance level of = 0.05, choose the correct conclusion regarding the null hypothesis.

A) There is not sufficient evidence to reject the null hypothesis that the population proportion is equal to 0.4.

B) There is not sufficient evidence to conclude

that the population proportion is significantly different from 0.4.

C) There is sufficient evidence to accept the null hypothesis that the population proportion is equal to 0.4.

D) There is sufficient

evidence to conclude that the population proportion is significantly different from 0.4.

5) A researcher believes that children who attend elementary school in a rural setting are more physically active

then children who attend elementary school in an urban setting. The researcher collects a random sample from each

population and records the proportion of children in each sample who reported participating in at least one hour of

rigorous activity a day. The data is summarized in the table below. Assume the all conditions for proceeding with a

two-sample test have been met.

Rural

n1 = 90

x1=74

Urban

n2= 78

x2= 55

Find the z

-statistic (rounded to the nearest hundredth) and p-

value (rounded to

the nearest thousandth) for this

hypothesis test. Using a 5% significance level, state the correct conclusion regarding the null hypothesis,

H0: prural = purban

A) z = 0.82, p = 0.073. There is sufficient

evidence to accept the null hypothesis.

B) z = 0.71, p = 0.073. There is sufficient evidence to reject the null hypothesis.

C) z = -

1.79, p = 0.037. There is insufficient evidence to reject the null hypothesis.

D) z = 1.79, p = 0.037. There is sufficient

evidence to reject the null hypothesis.

6)

Two movie reviewers, Sarah and Jessica, give movies "thumbs up" and "thumbs down" ratings. You sample 100 movies that they both have rated and find that they both gave "thumbs up" to 25 movies, both gave "thumbs down" to 30 movies, Sarah gave "thumbs up" and Jessica "thumb down" to 28 movies, and the remaining movies Sarah gave "thumbs down" and Jessica "thumbs up". Test whether there is a difference between them on how often they rate

movies as "thumbs up".

Test at = 0.05 level of significance.

Let p1=Sarah's data and p2=Jessica's data.

A) z = 1.56; For a two-sided test at = 0.05 level, there is insufficient evidence to reject the null hypothesis

because the cutoff z-value is at 1.96.

B) z = 1.96 There is sufficient evidence to accept the null hypothesis.

C) z = 1.56; For a two-sided test at = 0.05 level, there is insufficient evidence to reject the null

hypothesis because the cutoff z-value is at 1.96.

D) z = 1.96 There is sufficient evidence to reject the null hypothesis.

7) Construct a 98% confidence interval for p1- p2.

The sample statistics listed below are from independent samples.

Sample statistics:

n1= 1000,

x1= 250, and

n2= 1200,

x2 = 195

A) (0.581, 1.819)

B) (1.516, 3.021)

C) (-0.621, 0.781)

D) (0.047, 0.128)

8) A random sample of 100 students at a high

school was asked whether they would ask their father or mother for help

with a financial problem. A second sample of 100 different students was asked the same question regarding a dating

problem. Forty-three students in the first sample and 47 students in

the second sample replied that they turned to their

mother rather than their father for help. Construct a 98% confidence interval for p1- p2.

A) (-1.324, 1.521)

B) (-1.113, 1.311)

C) (-0.591, 0.762)

D) (-0.204, 0.124)