Question 1

Exhibit 9-2
  
-Refer to Exhibit 9-2.If the test is done at 95% confidence,the null hypothesis should

Accepted Answer

A) not be rejected 
B) be rejected 
C) Not enough information is given to answer this question. 
D) None of these alternatives is correct. 
A) not be rejected 
B) be rejected 
C) Not enough information is given to answer this question. 
D) None of these alternatives is correct.

Question 2

The power curve provides the probability of

Accepted Answer

A) correctly accepting the null hypothesis 
B) incorrectly accepting the null hypothesis 
C) correctly rejecting the alternative hypothesis 
D) correctly rejecting the null hypothesis 
A) correctly accepting the null hypothesis 
B) incorrectly accepting the null hypothesis 
C) correctly rejecting the alternative hypothesis 
D) correctly rejecting the null hypothesis

Question 3

A machine is designed to fill toothpaste tubes with 5.8 ounces of toothpaste.The manufacturer does not want any underfilling or overfilling.The correct hypotheses to be tested are

Accepted Answer

A) H0: $\mu$$\neq$ 5.8 Ha: $\mu$ = 5.8 B) H0: $\mu$ = 5.8 Ha: $\mu$$\neq$5.8 C) H0: $\mu$ > 5.8 Ha: $\mu$ $\le$ 5.8 D) H0: $\mu$ $\ge$ 5.8 Ha: $\mu$ < 5.8 A) H0: $\mu$$\neq$ 5.8 Ha: $\mu$ = 5.8 B) H0: $\mu$ = 5.8 Ha: $\mu$$\neq$5.8 C) H0: $\mu$ > 5.8 Ha: $\mu$ $\le$ 5.8 D) H0: $\mu$ $\ge$ 5.8 Ha: $\mu$ < 5.8

Question 4

A law enforcement agent believes that at least 88% of the drivers stopped on Saturday nights for speeding are under the influence of alcohol.A sample of 66 drivers who were stopped for speeding on a Saturday night was taken.Eighty percent of the drivers in the sample were under the influence of alcohol.
a.State the null and alternative hypotheses.
b.Compute the test statistic.
c.Using the p-value approach,test the hypotheses at the .05 level of significance.

Accepted Answer

a.H₀: P@#LAT-DLM&0.88 H_a

Question 5

The average price of homes sold in the U.S.in the past year was $220,000.A random sample of 81 homes sold this year showed an average price of $210,000.It is known that the standard deviation of the population is $36,000.At 95% confidence test to determine if there has been a significant decrease in the average price homes.
a.State the null and alternative hypotheses to be tested.
b.Compute the test statistic.
c.Determine the critical value for this test.
d.What do you conclude?
e.Compute the p-value.

Accepted Answer

a.H_o: @#LAT-DLM& @#LAT-DLM&220,000 H

Question 6

Which of the following does not need to be known in order to compute the p-value?

Accepted Answer

A) knowledge of whether the test is one-tailed or two-tailed 
B) the value of the test statistic 
C) the level of significance 
D) None of these alternatives is correct. 
A) knowledge of whether the test is one-tailed or two-tailed 
B) the value of the test statistic 
C) the level of significance 
D) None of these alternatives is correct.

Question 7

For a one-tailed hypothesis test (upper tail)the p-value is computed to be 0.034.If the test is being conducted at 95% confidence,the null hypothesis

Accepted Answer

A) could be rejected or not rejected depending on the sample size 
B) could be rejected or not rejected depending on the value of the mean of the sample 
C) is not rejected 
D) is rejected 
A) could be rejected or not rejected depending on the sample size 
B) could be rejected or not rejected depending on the value of the mean of the sample 
C) is not rejected 
D) is rejected

Question 8

The probability of making a Type II error is denoted by

Accepted Answer

A) $\alpha$ 
B) $\beta$ 
C) 1 - $\alpha$ 
D) 1 - $\beta$ 
A) $\alpha$ 
B) $\beta$ 
C) 1 - $\alpha$ 
D) 1 - $\beta$

Question 9

A carpet company advertises that it will deliver your carpet within 15 days of purchase.A sample of 49 past customers is taken.The average delivery time in the sample was 16.2 days.The standard deviation of the population ($\sigma$)is known to be 5.6 days.
a.State the null and alternative hypotheses.
b.Using the critical value approach,test to determine if their advertisement is legitimate.Let $\alpha$= .05.
c.Using the p-value approach,test the hypotheses at the 5% level of significance.

Accepted Answer

a.H₀: @#LAT-DLM& @#LAT-DLM&15 H_a</

Question 10

A sample of 30 cookies is taken to test the claim that each cookie contains at least 9 chocolate chips.The average number of chocolate chips per cookie in the sample was 7.8 with a standard deviation of 3.
a.State the null and alternative hypotheses.
b.Using the critical value approach,test the hypotheses at the 5% level of significance.
c.Using the p-value approach,test the hypothesis at the 5% level of significance.
d.Compute the probability of a Type II error if the true number of chocolate chips per cookie is 8.

Accepted Answer

a.H₀: @#LAT-DLM& @#LAT-DLM& 9 H_a: @#LAT-DLM& < 9

Question 11

In hypothesis testing,

Accepted Answer

A) the smaller the Type I error,the smaller the Type II error will be 
B) the smaller the Type I error,the larger the Type II error will be 
C) Type II error will not be effected by Type I error 
D) the sum of Type I and Ttype II errors must equal to 1 
A) the smaller the Type I error,the smaller the Type II error will be 
B) the smaller the Type I error,the larger the Type II error will be 
C) Type II error will not be effected by Type I error 
D) the sum of Type I and Ttype II errors must equal to 1

Question 12

Consider the following hypothesis test:
Ho: $\mu$   14
Ha:$\mu$  < 14
A sample of 64 provides a sample mean of 13 and a sample standard deviation of 4. 
a.Determine the standard error of the mean.
b.Compute the value of the test statistic.
c.Determine the p-value;and at 95% confidence,test the above hypotheses.

Accepted Answer

a.0.5
b.t = -2
c.p-v

Question 13

In hypothesis testing if the null hypothesis has been rejected when the alternative hypothesis has been true,

Accepted Answer

A) a Type I error has been committed 
B) a Type II error has been committed 
C) either a Type I or Type II error has been committed 
D) the correct decision has been made 
A) a Type I error has been committed 
B) a Type II error has been committed 
C) either a Type I or Type II error has been committed 
D) the correct decision has been made

Question 14

Two thousand numbers are selected randomly;960 were even numbers.
a.State the hypotheses to determine whether the proportion of odd numbers is significantly different from 50%.
b.Compute the test statistic.
c.At 90% confidence using the p-value approach,test the hypotheses.

Accepted Answer

a.H₀: P = 0.5 H

Question 15

Exhibit 9-4
The manager of a grocery store has taken a random sample of 100 customers.The average length of time it took the customers in the sample to check out was 3.1 minutes with a standard deviation of 0.5 minutes.We want to test to determine whether or not the mean waiting time of all customers is significantly more than 3 minutes.
-Refer to Exhibit 9-4.The test statistic is

Accepted Answer

A) 1.96 
B) 1.64 
C) 2.00 
D) 0.056 
A) 1.96 
B) 1.64 
C) 2.00 
D) 0.056

Question 16

From a population of cans of coffee marked "12 ounces," a sample of 50 cans was selected and the contents of each can were weighed.The sample revealed a mean of 11.8 ounces with a standard deviation of 0.5 ounces.
a.Formulate the hypotheses to test to see if the mean of the population is at least 12 ounces.
b.Compute the test statistic.
c.Using the p-value approach,what is your conclusion? Let $\alpha$= .05.

Accepted Answer

a.H₀: @#LAT-DLM& @#LAT-DLM& 12 H_a<

Question 17

The average manufacturing work week in metropolitan Chattanooga was 40.1 hours last year.It is believed that the recession has led to a reduction in the average work week.To test the validity of this belief,the hypotheses are

Accepted Answer

A) H0: $\mu$ a: $\mu$ $\ge$ 40.1 
B) H0:$\mu$ $\ge$  40.1 Ha: $\mu$ 0: $\mu$ > 40.1 Ha: $\mu$  $\le$ 40.1 
D) H0: $\mu$ = 40.1 Ha:$\mu$ $\neq$ 40.1 
A) H0: $\mu$ a: $\mu$ $\ge$ 40.1 
B) H0:$\mu$ $\ge$  40.1 Ha: $\mu$ 0: $\mu$ > 40.1 Ha: $\mu$  $\le$ 40.1 
D) H0: $\mu$ = 40.1 Ha:$\mu$ $\neq$ 40.1

Question 18

A producer of various kinds of batteries has been producing "D" size batteries with a life expectancy of 87 hours.Due to an improved production process,management believes that there has been an increase in the life expectancy of their "D" size batteries.A sample of 36 batteries showed an average life of 88.5 hours.Assume from past information that it is known that the standard deviation of the population is 9 hours.
a.Give the null and the alternative hypotheses.
b.Compute the test statistic.
c.At 99% confidence using the critical value approach,test management's belief.
d.What is the p-value associated with the sample results? What is your conclusion based on the p-value?

Accepted Answer

a.H_o: @#LAT-DLM& < 87 H_a@#LAT-DLM& >

Question 19

Consider the following hypothesis test:
Ho: $\mu$  40
Ha: $\mu$< 40
A sample of 49 provides a sample mean of 38 and a sample standard deviation of 7. 
a.Determine the standard error of the mean.
b.Compute the value of the test statistic.
c.Determine the p-value;and at 95% confidence,test the above hypotheses.

Accepted Answer

a.1
b.t = -2
c.p-val

Question 20

In a lower one-tail hypothesis test situation,the p-value is determined to be 0.2.If the sample size for this test is 51,the t statistic has a value of

Accepted Answer

A) 0.849 
B) -0.849 
C) 1.299 
D) -1.299 
A) 0.849 
B) -0.849 
C) 1.299 
D) -1.299

Exhibit 9-2 -Refer to Exhibit 9-2.If the test is done at 95% confidence,the null hypothesis should

The power curve provides the probability of

A machine is designed to fill toothpaste tubes with 5.8 ounces of toothpaste.The manufacturer does not want any underfilling or overfilling.The correct hypotheses to be tested are

Which of the following does not need to be known in order to compute the p-value?

For a one-tailed hypothesis test (upper tail)the p-value is computed to be 0.034.If the test is being conducted at 95% confidence,the null hypothesis

The probability of making a Type II error is denoted by

In hypothesis testing,

In hypothesis testing if the null hypothesis has been rejected when the alternative hypothesis has been true,

Two thousand numbers are selected randomly;960 were even numbers. a.State the hypotheses to determine whether the proportion of odd numbers is significantly different from 50%. b.Compute the test statistic. c.At 90% confidence using the p-value approach,test the hypotheses.

The average manufacturing work week in metropolitan Chattanooga was 40.1 hours last year.It is believed that the recession has led to a reduction in the average work week.To test the validity of this belief,the hypotheses are

In a lower one-tail hypothesis test situation,the p-value is determined to be 0.2.If the sample size for this test is 51,the t statistic has a value of

Data and Statistics

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Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Statistical Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit and Independence

Analysis of Variance and Experimental Design

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Exam 9: Hypothesis Tests

Exhibit 9-2 -Refer to Exhibit 9-2.If the test is done at 95% confidence,the null hypothesis should

The power curve provides the probability of

A machine is designed to fill toothpaste tubes with 5.8 ounces of toothpaste.The manufacturer does not want any underfilling or overfilling.The correct hypotheses to be tested are

Which of the following does not need to be known in order to compute the p-value?

For a one-tailed hypothesis test (upper tail)the p-value is computed to be 0.034.If the test is being conducted at 95% confidence,the null hypothesis

The probability of making a Type II error is denoted by

In hypothesis testing,

In hypothesis testing if the null hypothesis has been rejected when the alternative hypothesis has been true,

Two thousand numbers are selected randomly;960 were even numbers. a.State the hypotheses to determine whether the proportion of odd numbers is significantly different from 50%. b.Compute the test statistic. c.At 90% confidence using the p-value approach,test the hypotheses.

The average manufacturing work week in metropolitan Chattanooga was 40.1 hours last year.It is believed that the recession has led to a reduction in the average work week.To test the validity of this belief,the hypotheses are

In a lower one-tail hypothesis test situation,the p-value is determined to be 0.2.If the sample size for this test is 51,the t statistic has a value of

Data and Statistics

Descriptive Statistics: Tabular and Graphical Presentations

Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Statistical Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit and Independence

Analysis of Variance and Experimental Design

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Index Numbers

Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Decision Analysis

Sample Survey

Filters