devry math399 final exam latest 2016 july

devry math399n final exam latest 2016 july

1.

The equation used to predict college GPA (range 0-4.0) is

y=0.23+0.52x1+0.002x2,

where

x1

is high school GPA (range 0-4.0) and

x2

is college board score (range 200-800). Use the multiple regression equation to predict college GPA for a high school GPA of

3.2

and a college board score of

400.

The predicted college GPA for a high school GPA of

3.2

and a college board score of

400

is

(Round to the nearest tenth as needed.)

2.

Match the plot with a possible description of the sample.

Choose the correct answer below.

A.

Top speeds left parenthesis in miles per hour of a sample of sports cars

.

B.

Ages in years of a sample of residents of a retirement home

C.

Time in hours spent watching TV in a day for a sample of teenagers

D.

Number of home runs hit in a season for a sample of baseball players

3.

The ages of 10 brides at their first marriage are given below. Complete parts (a) and (b) below.

30.8??

37.9??

28.7??

33.2??

43.1??

33.9??

29.3??

30.9??

30.3??

30.4??

(a) Find the range of the data set.

Range=

(Round to the nearest tenth as needed.)

(b) Change

43.1

to

64.2

and find the range of the new data set.

Range=

(Round to the nearest tenth as needed.)

4.

In a sample of

1200

U.S. adults,

204

dine out at a resaurant more than once per week.

Two

U.S. adults are selected at random from the population of all U.S. adults without replacement. Assuming the sample is representative of all U.S. adults, complete parts (a) through (d).

(a) Find the probability that both adults dine out more than once per week.

The probability that both adults dine out more than once per week is

(Round to three decimal places as needed.)

(b) Find the probability that neither adult dines out more than once per week.

The probability that neither adult dines out more than once per week is

(Round to three decimal places as needed.)

(c) Find the probability that at least one of the two adults dines out more than once per week.

The probability that at least one of the two adults dines out more than once per week is

(Round to three decimal places as needed.)

(d) Which of the events can be considered unusual? Explain. Select all that apply.

A.

The event in part (c) is unusual because its probability is less than or equal to 0.05.

B.

The event in part a is unusual because its probability is less than or equal to 0.05

.

C.

The event in part (b) is unusual because its probability is less than or equal to 0.05.

D.

None of these events are unusual

Question is complete.

5.

The table below shows the results of a survey that asked

2849

people whether they are involved in any type of charity work. A person is selected at random from the sample. Complete parts (a) through (e).

Frequently??? Occasionally Not at all Total

Male 226 451 795 1472

Female 204 430 743 1377

Total 430 881 1538 2849

(a) Find the probability that the person is frequently or occasionally involved in charity work.

P(being frequently involved or being occasionally involved)=

(Round to the nearest thousandth as needed.)

(b) Find the probability that the person is female or not involved in charity work at all.

P(being female or not being involved)=

(Round to the nearest thousandth as needed.)

(c) Find the probability that the person is male or frequently involved in charity work.

P(being male or being frequently involved

(Round to the nearest thousandth as needed.)

(d) Find the probability that the person is female or not frequently involved in charity work.

P(being female or not being frequently involved)=

(Round to the nearest thousandth as needed.)

(e) Are the events "being female" and "being frequently involved in charity work" mutually exclusive? Explain.

6.

58%

of men consider themselves professional baseball fans. You randomly select 10 men and ask each if he considers himself a professional baseball fan. Find the probability that the number who consider themselves baseball fans is (a) exactly five, (b) at least six, and (c) less than four.

(a)

P(5)=

(Round to three decimal places as needed.)

(b)

P(x?6)=

(Round to three decimal places as needed.)

(c)

P(x<4)=

(Round to three decimal places as needed.)

7.

A machine cuts plastic into sheets that are

45

feet

(540

inches) long. Assume that the population of lengths is normally distributed. Complete parts (a) and (b).

(a)

The company wants to estimate the mean length the machine is cutting the plastic within

0.25

inch. Determine the minimum sample size required to construct a

95%

confidence interval for the population mean. Assume the population standard deviation is

0.50

inch.

n=

(Round up to the nearest whole number as needed.)

(b)

Repeat part (a) using an error tolerance of

0.125

inch.

n=

(Round up to the nearest whole number as needed.)

Which error tolerance requires a larger sample size? Explain.

A.

The tolerance

E=0.125

inch requires a larger sample size. As error size increases, a larger sample must be taken to ensure the desired accuracy.

B.

The tolerance

E=0.125

inch requires a larger sample size. As error size decreases, a larger sample must be taken to ensure the desired accuracy.

C.

The tolerance

E=0.25

inch requires a larger sample size. As error size decreases, a larger sample must be taken to ensure the desired accuracy.

D.

The tolerance

E=0.25

inch requires a larger sample size. As error size increases, a larger sample must be taken to ensure the desired accuracy.

8.

The number of credits being taken by a sample of 13 full-time college students are listed below. Find the mean, median, and mode of the data, if possible. If any measure cannot be found or does not represent the center of thedata, explain why.

8??

10??

11??

11??

8??

9??

7??

7??

7??

7??

7??

7??

8??

Find the mean. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.

The mean is

(Type an integer or decimal rounded to one decimal place as needed.)

Your answer is correct.

B.

The data set does not have a mean.

Does the mean represent the center of the data?

A.

The mean represents the center.

B.

The mean does not represent the center because it is not a data value.

C.

The mean does not represent the center because it is the largest data value.

D.

The mean does not represent the center because it is the smallest data value.

E.

The data set does not have a mean.

Find the median. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.

The median is

(Type an integer or decimal rounded to one decimal place as needed.)

.

B.

The data set does not have a median.

Does the median represent the center of the data?

A.

The median represents the center.

B.

The median does not represent the center because it is the largest data value.

C.

The median does not represent the center because it is not a data value.

D.

The median does not represent the center because it is the smallest data value.

E.

The data set does not have a median.

Find the mode. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.

The mode(s) is/are

(Type an integer or decimal rounded to one decimal place as needed. Use a comma to separate answers as needed.)

.

B.

The data set does not have a mode.

Does (Do) the mode(s) represent the center of the data?

A.

The mode(s) represent(s) the center.

B.

The data set does not have a mode.

C.

The mode(s) does (do) not represent the center because it (one) is the

largest

data value.

D.

The mode(s) does (do) not represent the center because it (one) is the

smallest

data value.

E.

The mode(s) does (do) not represent the center because it (they) is (are) not a data value.

Question is complete.

9.

In a survey of

2303

adults,

725

say they believe in UFOs.

Construct a

95%

confidence interval for the population proportion of adults who believe in UFOs.

A

95%

confidence interval for the population proportion is

left parenthesis nothing comma nothing right parenthesis

(Round to three decimal places as needed.)

Interpret your results. Choose the correct answer below.

A.

With

95%

probability, the population proportion of adults who do not believe in UFOs is between the endpoints of the given confidence interval.

B.

With

95%

confidence, it can be said that the sample proportion of adults who believe in UFOs is between the endpoints of the given confidence interval.

C.

With

95%

confidence, it can be said that the population proportion of adults who believe in UFOs is between the endpoints of the given confidence interval.

D.

The endpoints of the given confidence interval shows that

95%

of adults believe in UFOs.

10.

The time spent (in days) waiting for a heart transplant for people ages 35-49 can be approximiated by the normal distribution, as shown in the figure to the right.

(a) What waiting time represents the

5th

percentile?

(b) What waiting time represents the third quartile?

(a) The waiting time that represents the

5th

percentile is

days.

(Round to the nearest integer as needed.)

(b) The waiting time that represents the third quartile is

days.

(Round to the nearest integer as needed.)

11.

Heights of men on a baseball team have a bell-shaped distribution with a mean of

175 cm

and a standard deviation of

5 cm

Using the empirical rule, what is the approximate percentage of the men between the following values?

a.

170

cm and

180

cm

b.

160160

cm and

190

cm

a.

of the men are between

170

cm and

180

cm.

(Round to one decimal place as needed.)

b.

of the men are between

160

cm and

190

cm.

(Round to one decimal place as needed.)

12.

An annual survey of first-year college students asks

000273,000

students about their attitudes on a variety of subjects. According to a recent survey,

58%

of first-year students believe that abortion should be legal. Use a 0.05 significance level to test the claim that over half of all first-year students believe that abortion should be legal.

Formulate the null and alternative hypotheses. Choose the correct answer below.

A.

H0:

p<0.5

Ha:

p=0.5

B.

H0:

p=0.5

Ha:

p<0.5

C.

H0:

p=0.5

Ha:

p>0.5

D.

H0:

p=0.5

Ha:

p?0.5

Find the test statistic.

z=

(Round to two decimal places as needed.)

Find the P-value for the found test statistic.

P-value=

(Round to four decimal places as needed.)

State the conclusion. Choose the correct answer below.

A.

Do not reject

H0.

There is insufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

B.

Do not reject

H0.

There is sufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

C.

Reject

H0.

There is insufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

D.

Reject

H0.

There is sufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

13

The table below shows the results of a survey in which

141

men and

146

women workers ages 25 to 64 were asked if they have at least one month's income set aside for emergencies. Complete parts (a) through (d).

Men Women Total

Less than one month's income 65 84 149

One month's income or more

76 62 138

Total 141 146 287

(a) Find the probability that a randomly selected worker has one month's income or more set aside for emergencies.

The probability is

(Round to the nearest thousandth as needed.)

(b) Given that a randomly selected worker is a male, find the probability that the worker has less than one month's income.

The probability is

(Round to the nearest thousandth as needed.)

(c) Given that a randomly selected worker has one month's income or more, find the probability that the worker is a female.

The probability is

(Round to the nearest thousandth as needed.)

(d) Are the events "having less than one month's income saved" and "being male" independent or dependent?

Dependent

Independent

14.

Construct the confidence interval for the population mean

?.

cequals=0.90,

x=9.9,

?=0.5,

and

n=58

A

90%

confidence interval for

?

is

(Round to two decimal places as needed.)

15.

Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Assume the population of interest is the student body at a university.

Questioning students as they leave

an athletic facility,

a researcher asks

350

students about their

dating

habits.

What type of sampling is used?

A.

Systematic sampling is used, because students are selected from a list, with a fixed interval between students on the list.

B.

Cluster sampling is used, because students are divided into groups, groups are chosen at random, and every student in one of those groups is sampled.

C.

Convenience sampling is used, because students are chosen due to convenience of location.

D.

Stratified sampling is used, because students are divided into groups, and students are chosen at random from these groups.

E.

Simple random sampling is used, because students are chosen at random.

What potential sources of bias are present, if any? Select all that apply.

A.

University students may not be representative of all people in their age group.

B.

The sample only consists of members of the population that are easy to get. These members may not be representative of the population.

.

C.

Because of the personal nature of the question, students may not answer honestly.

D.

There are no potential sources of bias.

16.

Use the value of the linear correlation coefficient to calculate the coefficient of determination. What does this tell you about the explained variation of the data about the regression line? About the unexplained variation?

r=0.953

Calculate the coefficient of determination.

(Round to three decimal places as needed.)

What does this tell you about the explained variation of the data about the regression line?

of the variation can be explained by the regression line.

(Round to one decimal place as needed.)

About the unexplained variation?

of the variation is unexplained and is due to other factors or to sampling error.

(Round to one decimal place as needed.)

devry math399n final exam latest 2016 july

1.

The equation used to predict college GPA (range 0-4.0) is

y=0.23+0.52x1+0.002x2,

where

x1

is high school GPA (range 0-4.0) and

x2

is college board score (range 200-800). Use the multiple regression equation to predict college GPA for a high school GPA of

3.2

and a college board score of

400.

The predicted college GPA for a high school GPA of

3.2

and a college board score of

400

is

2.7.

(Round to the nearest tenth as needed.)

2.

Match the plot with a possible description of the sample. 180190200210220

x y graph

Choose the correct answer below.

A.

Top speeds left parenthesis in miles per hour of a sample of sports cars

.

B.

Ages in years of a sample of residents of a retirement home

C.

Time in hours spent watching TV in a day for a sample of teenagers

D.

Number of home runs hit in a season for a sample of baseball players

3.

The ages of 10 brides at their first marriage are given below. Complete parts (a) and (b) below.

30.8??

37.9??

28.7??

33.2??

43.1??

33.9??

29.3??

30.9??

30.3??

30.4??

(a) Find the range of the data set.

Range= 14.4

(Round to the nearest tenth as needed.)

(b) Change

43.1

to

64.2

and find the range of the new data set.

Range= 35.5

(Round to the nearest tenth as needed.)

4.

In a sample of

1200

U.S. adults,

204

dine out at a resaurant more than once per week.

Two

U.S. adults are selected at random from the population of all U.S. adults without replacement. Assuming the sample is representative of all U.S. adults, complete parts (a) through (d).

(a) Find the probability that both adults dine out more than once per week.

The probability that both adults dine out more than once per week is

0.029.

(Round to three decimal places as needed.)

(b) Find the probability that neither adult dines out more than once per week.

The probability that neither adult dines out more than once per week is

0.689.

(Round to three decimal places as needed.)

(c) Find the probability that at least one of the two adults dines out more than once per week.

The probability that at least one of the two adults dines out more than once per week is

0.311.

(Round to three decimal places as needed.)

(d) Which of the events can be considered unusual? Explain. Select all that apply.

A.

The event in part (c) is unusual because its probability is less than or equal to 0.05.

B.

The event in part a is unusual because its probability is less than or equal to 0.05

.

C.

The event in part (b) is unusual because its probability is less than or equal to 0.05.

D.

None of these events are unusual

Question is complete.

5.

The table below shows the results of a survey that asked

2849

people whether they are involved in any type of charity work. A person is selected at random from the sample. Complete parts (a) through (e).

Frequently??? Occasionally Not at all Total

Male 226 451 795 1472

Female 204 430 743 1377

Total 430 881 1538 2849

(a) Find the probability that the person is frequently or occasionally involved in charity work.

P(being frequently involved or being occasionally involved)= 0.460

(Round to the nearest thousandth as needed.)

(b) Find the probability that the person is female or not involved in charity work at all.

P(being female or not being involved)= 0.762

(Round to the nearest thousandth as needed.)

(c) Find the probability that the person is male or frequently involved in charity work.

P(being male or being frequently involved)= 0.588

(Round to the nearest thousandth as needed.)

(d) Find the probability that the person is female or not frequently involved in charity work.

P(being female or not being frequently involved)= 0.921

(Round to the nearest thousandth as needed.)

(e) Are the events "being female" and "being frequently involved in charity work" mutually exclusive? Explain.

6.

58%

of men consider themselves professional baseball fans. You randomly select 10 men and ask each if he considers himself a professional baseball fan. Find the probability that the number who consider themselves baseball fans is (a) exactly five, (b) at least six, and (c) less than four.

(a)

P(5)= 0.216

(Round to three decimal places as needed.)

(b)

P(x?6)= 0.582

(Round to three decimal places as needed.)

(c)

P(x<4)= 0.071

(Round to three decimal places as needed.)

7.

A machine cuts plastic into sheets that are

45

feet

(540

inches) long. Assume that the population of lengths is normally distributed. Complete parts (a) and (b).

(a)

The company wants to estimate the mean length the machine is cutting the plastic within

0.25

inch. Determine the minimum sample size required to construct a

95%

confidence interval for the population mean. Assume the population standard deviation is

0.50

inch.

n= 16

(Round up to the nearest whole number as needed.)

(b)

Repeat part (a) using an error tolerance of

0.125

inch.

n= 62

(Round up to the nearest whole number as needed.)

Which error tolerance requires a larger sample size? Explain.

A.

The tolerance

E=0.125

inch requires a larger sample size. As error size increases, a larger sample must be taken to ensure the desired accuracy.

B.

The tolerance

E=0.125

inch requires a larger sample size. As error size decreases, a larger sample must be taken to ensure the desired accuracy.

C.

The tolerance

E=0.25

inch requires a larger sample size. As error size decreases, a larger sample must be taken to ensure the desired accuracy.

D.

The tolerance

E=0.25

inch requires a larger sample size. As error size increases, a larger sample must be taken to ensure the desired accuracy.

8.

The number of credits being taken by a sample of 13 full-time college students are listed below. Find the mean, median, and mode of the data, if possible. If any measure cannot be found or does not represent the center of thedata, explain why.

8??

10??

11??

11??

8??

9??

7??

7??

7??

7??

7??

7??

8??

Find the mean. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.

The mean is

8.2.

(Type an integer or decimal rounded to one decimal place as needed.)

Your answer is correct.

B.

The data set does not have a mean.

Does the mean represent the center of the data?

A.

The mean represents the center.

B.

The mean does not represent the center because it is not a data value.

C.

The mean does not represent the center because it is the largest data value.

D.

The mean does not represent the center because it is the smallest data value.

E.

The data set does not have a mean.

Find the median. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.

The median is

8.

(Type an integer or decimal rounded to one decimal place as needed.)

.

B.

The data set does not have a median.

Does the median represent the center of the data?

A.

The median represents the center.

B.

The median does not represent the center because it is the largest data value.

C.

The median does not represent the center because it is not a data value.

D.

The median does not represent the center because it is the smallest data value.

E.

The data set does not have a median.

Find the mode. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.

The mode(s) is/are

7

(Type an integer or decimal rounded to one decimal place as needed. Use a comma to separate answers as needed.)

.

B.

The data set does not have a mode.

Does (Do) the mode(s) represent the center of the data?

A.

The mode(s) represent(s) the center.

B.

The data set does not have a mode.

C.

The mode(s) does (do) not represent the center because it (one) is the

largest

data value.

D.

The mode(s) does (do) not represent the center because it (one) is the

smallest

data value.

E.

The mode(s) does (do) not represent the center because it (they) is (are) not a data value.

Question is complete.

9.

In a survey of

2303

adults,

725

say they believe in UFOs.

Construct a

95%

confidence interval for the population proportion of adults who believe in UFOs.

A

95%

confidence interval for the population proportion is

left parenthesis nothing comma nothing right parenthesis( 0.296, 0.334).

(Round to three decimal places as needed.)

Interpret your results. Choose the correct answer below.

A.

With

95%

probability, the population proportion of adults who do not believe in UFOs is between the endpoints of the given confidence interval.

B.

With

95%

confidence, it can be said that the sample proportion of adults who believe in UFOs is between the endpoints of the given confidence interval.

C.

With

95%

confidence, it can be said that the population proportion of adults who believe in UFOs is between the endpoints of the given confidence interval.

D.

The endpoints of the given confidence interval shows that

95%

of adults believe in UFOs.

10.

The time spent (in days) waiting for a heart transplant for people ages 35-49 can be approximiated by the normal distribution, as shown in the figure to the right.

(a) What waiting time represents the

5th

percentile?

(b) What waiting time represents the third quartile?

(a) The waiting time that represents the

5th

percentile is

166

days.

(Round to the nearest integer as needed.)

(b) The waiting time that represents the third quartile is

220

days.

(Round to the nearest integer as needed.)

11.

Heights of men on a baseball team have a bell-shaped distribution with a mean of

175 cm

and a standard deviation of

5 cm

Using the empirical rule, what is the approximate percentage of the men between the following values?

a.

170

cm and

180

cm

b.

160160

cm and

190

cm

a.

68.3%

of the men are between

170

cm and

180

cm.

(Round to one decimal place as needed.)

b.

99.7%

of the men are between

160

cm and

190

cm.

(Round to one decimal place as needed.)

12.

An annual survey of first-year college students asks

000273,000

students about their attitudes on a variety of subjects. According to a recent survey,

58%

of first-year students believe that abortion should be legal. Use a 0.05 significance level to test the claim that over half of all first-year students believe that abortion should be legal.

Formulate the null and alternative hypotheses. Choose the correct answer below.

A.

H0:

p<0.5

Ha:

p=0.5

B.

H0:

p=0.5

Ha:

p<0.5

C.

H0:

p=0.5

Ha:

p>0.5

D.

H0:

p=0.5

Ha:

p?0.5

Find the test statistic.

z= 83.60

(Round to two decimal places as needed.)

Find the P-value for the found test statistic.

P-value= 0.0000

(Round to four decimal places as needed.)

State the conclusion. Choose the correct answer below.

A.

Do not reject

H0.

There is insufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

B.

Do not reject

H0.

There is sufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

C.

Reject

H0.

There is insufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

D.

Reject

H0.

There is sufficient evidence to support the claim that over half of all first-year students believe that abortion should be legal.

13

The table below shows the results of a survey in which

141

men and

146

women workers ages 25 to 64 were asked if they have at least one month's income set aside for emergencies. Complete parts (a) through (d).

Men Women Total

Less than one month's income 65 84 149

One month's income or more

76 62 138

Total 141 146 287

(a) Find the probability that a randomly selected worker has one month's income or more set aside for emergencies.

The probability is

0.481.

(Round to the nearest thousandth as needed.)

(b) Given that a randomly selected worker is a male, find the probability that the worker has less than one month's income.

The probability is

0.461.

(Round to the nearest thousandth as needed.)

(c) Given that a randomly selected worker has one month's income or more, find the probability that the worker is a female.

The probability is

0..449.

(Round to the nearest thousandth as needed.)

(d) Are the events "having less than one month's income saved" and "being male" independent or dependent?

Dependent

Independent

14.

Construct the confidence interval for the population mean

?.

cequals=0.90,

x=9.9,

?=0.5,

and

n=58

A

90%

confidence interval for

?

is

.( 9.79, 10.01).

(Round to two decimal places as needed.)

15.

Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Assume the population of interest is the student body at a university.

Questioning students as they leave

an athletic facility,

a researcher asks

350

students about their

dating

habits.

What type of sampling is used?

A.

Systematic sampling is used, because students are selected from a list, with a fixed interval between students on the list.

B.

Cluster sampling is used, because students are divided into groups, groups are chosen at random, and every student in one of those groups is sampled.

C.

Convenience sampling is used, because students are chosen due to convenience of location.

D.

Stratified sampling is used, because students are divided into groups, and students are chosen at random from these groups.

E.

Simple random sampling is used, because students are chosen at random.

What potential sources of bias are present, if any? Select all that apply.

A.

University students may not be representative of all people in their age group.

B.

The sample only consists of members of the population that are easy to get. These members may not be representative of the population.

.

C.

Because of the personal nature of the question, students may not answer honestly.

D.

There are no potential sources of bias.

16.

Use the value of the linear correlation coefficient to calculate the coefficient of determination. What does this tell you about the explained variation of the data about the regression line? About the unexplained variation?

r=0.953

Calculate the coefficient of determination.

0.908

(Round to three decimal places as needed.)

What does this tell you about the explained variation of the data about the regression line?

90.8%

of the variation can be explained by the regression line.

(Round to one decimal place as needed.)

About the unexplained variation?

9.2%

of the variation is unexplained and is due to other factors or to sampling error.

(Round to one decimal place as needed.)

17.

The lengths of time (in years) it took a random sample of

32

former smokers to quit smoking permanently are listed. Assume the population standard deviation is

5.3

years. At

?=0.01,

is there enough evidence to reject the claim that the mean time it takes smokers to quit smoking permanently is

13

years? Complete parts (a) through (e).

18.3 11.6 14.4 11.9 10.4 12.3 7.9 14.4

11.6 13.4 22.8 18.7 8.5 12.7 20.7 20.8

22.9 17.1 16.3 14.2 8.4 13.5 21.3 17.8

12.3 10.6 10.9 13.7 14.4 9.2 14.5 18.6

(a) Identify the claim and state the null hypothesis and alternative hypothesis.

A.

H0:

?=13

(claim)

Ha:

??1313

.

B.

H0:

??13

(claim)

Ha:

?=13

C.

H0:

??13

(claim)

Ha:

?>1313

D.

H0:

??1313

(claim)

Ha:

?<13

E.

H0:

?>1313

(claim)

Ha:

??13

F.

H0:

?>1313

Ha:

??13

(claim)

(b) Identify the standardized test statistic. Use technology.

z= ??

(Round to two decimal places as needed.)

(c) Find the P-value. Use technology.

P=

(Round to three decimal places as needed.)

(d) Decide whether to reject or fail to reject the null hypothesis and (e) interpret the decision in the context of the original claim at the

11%

level of significance.

A.

Reject

H0.

There

is not

sufficient evidence to reject the claim that the mean time it takes smokers to quit smoking permanently is

13

years.

B.

Fail to reject

H0.

There

is not

sufficient evidence to reject the claim that the mean time it takes smokers to quit smoking permanently is

13

years.

C.

Fail to reject

H0.

There

is

sufficient evidence to reject the claim that the mean time it takes smokers to quit smoking permanently is

13

years.

D.

Reject

H0.

There

is

sufficient evidence to reject the claim that the mean time it takes smokers to quit smoking permanently is

13

years.

Question is complete.

18.

The following appear on a physician's intake form. Identify the level of measurement of the data.

left parenthesis a right parenthesis nbsp(a) Marital status (b) TemperatureTemperature

left parenthesis c right parenthesis(c) Time since last visitTime since last visit left parenthesis d right parenthesis nbsp(d) Pain level left parenthesis scale of 0 to 10 right parenthesisPain level (scale of 0 to 10)

(a) What is the level of measurement for

"Marital statusMarital status"?

Interval

Nominal

Ordinal

Ratio

(b) What is the level of measurement for

"TemperatureTemperature"?

Nominal

Ordinal

Interval

Ratio

(c) What is the level of measurement for

"Time since last visitTime since last visit"?

Interval

Nominal

Ordinal

Ratio

(d) What is the level of measurement for

"Pain level left parenthesis scale of 0 to 10 right parenthesisPain level (scale of 0 to 10)"?

Nominal

Ordinal

Interval

Ratio

Question is complete.

19.

For the statement below, write the claim as a mathematical statement. State the null and alternative hypotheses and identify which represents the claim.

According to a recent survey,

24%

of college students

nothingown

a credit card.

Write the claim as a mathematical statement.

A.

p=0.24

B.

p>0.24

C.

p?0.24

D.

p<0.24

E.

p?0.2424

F.

p?0.24

Choose the correct null and alternative hypotheses below.

A.

H0:

p=0.24

Ha:

p?0.24

.

B.

H0:

p?0.24

Ha:

p<0.2424

C.

H0:

p<0.2424

Ha:

p?0.24

D.

H0:

p>0.24

Ha:

p?0.24

E.

H0:

p?0.24

Ha:

p>0.24

F.

H0:

p?0.24

Ha:

p=0.24

Identify which is the claim.

The null hypothesis

H0:

p?0.24

is the claim.

The null hypothesis

H0:p?0.24

is the claim.

The

alternative

hypothesis

Ha:

p?0.2424

is the claim.

The

null

hypothesis

H0:

p=0.24

is the claim.

.

The alternative hypothesis

Ha:

p<0.24

is the claim.

The alternative hypothesis

Ha:

p>0.24

is the claim.

Question is complete.

20

Use the normal distribution of fish lengths for which the mean is

8

inches and the standard deviation is

5

inches. Assume the variable x is normally distributed.

left parenthesis a right parenthesis(a) What percent of the fish are longer than

12

inches?

left parenthesis b right parenthesis(b) If

300

fish are randomly selected, about how many would you expect to be shorter than

6

inches?

left parenthesis a right parenthesis(a)

Approximately

21.19%

of fish are longer than

12

inches.

(Round to two decimal places as needed.)

left parenthesis b right parenthesis(b)

You would expect approximately

104

fish to be shorter than

6

inches.

(Round to the nearest fish.)??

21.

Assume the Poisson distribution applies. Use the given mean to find the indicated probability.

Find

P(5)

when

?=8.

P(5)= 0.092

(Round to the nearest thousandth as needed.)

22.

The accompanying data are the length (in centimeters) and girths (in centimeters) of

12

harbor seals. Find the equation of the regression line. Then construct a scatter plot of the data and draw the regression line. Then use the regression equation to predict the value of y for each of the given x-values, if meaningful. If the x-value is not meaningful to predict the value of y, explain why not.

(a)

x=140

cm (b)

x=172

cm (c)

x=164

cm

d)

x=158

cm

(d)

xequals=158158

cm

LOADING...

Click the icon to view the table of lengths and girths.

The equation of the regression line is

y=

(Round to two decimal places as needed.)

Construct a scatter plot of the data and draw the regression line. Plot length on the horizontal axis and girth on the vertical axis. Choose the correct graph below.

A.

font size decreased by 3 120120

font size decreased by 3 180180

font size decreased by 3 100100

font size decreased by 3 140140

font size decreased by 3 00

x y graph

Your answer is correct.

B.

font size decreased by 3 120120

font size decreased by 3 180180

font size decreased by 3 100100

font size decreased by 3 140140

font size decreased by 3 00

x y graph

C.

font size decreased by 3 120120

font size decreased by 3 180180

font size decreased by 3 100100

font size decreased by 3 140140

font size decreased by 3 00

x y graph

D.

font size decreased by 3 120120

font size decreased by 3 180180

font size decreased by 3 100100

font size decreased by 3 140140

font size decreased by 3 00

x y graph

(a) Predict the girth for a length of

140

cm, if it is meaningful. Select the correct choice below and, if necessary, fill in the answer box within your choice.

A.

y=

cm (Round to two decimal places as needed.)

B.

It is not meaningful to predict this value of y because

x=140

is inside the range of the original data.

C.

It is not meaningful to predict this value of y because

x=140

is not an x-value in the original data.

(b) Predict the girth for a length of

172

cm, if it is meaningful. Select the correct choice below and, if necessary, fill in the answer box within your choice.

A.

y= nothing

cm (Round to two decimal places as needed.)

B.

It is not meaningful to predict this value of y because

x=

is well outside the range of the original data.

C.

It is not meaningful to predict this value of y because

x=172

is not an x-value in the original data.

(c) Predict the girth for a length of

164

cm, if it is meaningful. Select the correct choice below and, if necessary, fill in the answer box within your choice.

A.

y =

cm (Round to two decimal places as needed.)

B.

It is not meaningful to predict this value of y because

X=164

is inside the range of the original data.

C.

It is not meaningful to predict this value of y because

x=164

is not an x-value in the original data.

(d) Predict the girth for a length of

158

cm, if it is meaningful. Select the correct choice below and, if necessary, fill in the answer box within your choice.

A.

y =

cm (Round to two decimal places as needed.)

B.

It is not meaningful to predict this value of y because

x=158

is inside the range of the original data.

C.

It is not meaningful to predict this value of y because

x=158

is not an x-value in the original data.

23.

Use technology to (a) construct and graph a probability distribution and (b) describe its shape.

The number of computers per household in a small town

Computers 0 1 2 3

Households 305 275 98 21

(a) Construct the probability distribution by completing the table below.

x P(x)

0

1

2

3

(Round to three decimal places as needed.)

Choose the correct graph of the probability distribution.

A.

01230.10.20.30.40.5Number of ComputersP(x)x

x y graph

B.

01230.10.20.30.40.5Number of ComputersP(x)x

x y graph

C.

01230.10.20.30.40.5Number of ComputersP(x)x

x y graph

(b) Describe the distribution's shape. Choose the correct answer below.

skewed left

symmetric

skewed right

Question is complete. Tap on the red indicators to see incorrect answers.

24.

The mean height of women in a country (ages

20?29)

is

63.6

inches. A random sample of

50

women in this age group is selected. What is the probability that the mean height for the sample is greater than

64

inches? Assume

?=2.84.

The probability that the mean height for the sample is greater than

64

inches is

(Round to four decimal places as needed.)