1 of 40 2.5 Points A researcher wants to check the claim that convicted burglars spend an average of 18.7 months in jail. She takes a random sample of 35 such cases from court files and finds that months. Assume that the population standard deviation is 7 months. Test the null hypothesis that = 18.7 at the 0.05 significance level. A. Do not reject the null hypothesis and conclude that the claim that the mean is different from 18.7 months is supported. B. Do not reject the null hypothesis and conclude that the claim that the mean is different from 18.7 months cannot be supported. C. Reject the null hypothesis and conclude that the claim that the mean is different from 18.7 months is supported. D. Reject the null hypothesis and conclude that the claim that the mean is different from 18.7 months cannot be supported. Reset Selection Question 3 of 40 2.5 Points At one school, the mean amount of time that tenth-graders spend watching television each week is 18.4 hours. The principal introduces a campaign to encourage the students to watch less television. One year later, the principal wants to perform a hypothesis test to determine whether the average amount of time spent watching television per week has decreased. Formulate the null and alternative hypotheses for the study described. A. Ho: = 18.4 hours H a : 18.4 hours B. Ho: = 18.4 hours H a : < 18.4 hours C. Ho: 18.4 hours H a : < 18.4 hours D. Ho: = 18.4 hours H a : > 18.4 hours Question 5 of 40 2.5 Points The owner of a football team claims that the average attendance at home games is over 3000, 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 non-technical terms. A. There is sufficient evidence to support the claim that the mean attendance is greater than 3000. B. There is sufficient evidence to support the claim that the mean attendance is equal to 3000. C. There is not sufficient evidence to support the claim that the mean attendance is greater than 3000. D. There is not sufficient evidence to support the claim that the mean attendance is less than 3000. Reset Selection Question 8 of 40 2.5 Points without computing a P-value, determine whether the alternate hypothesis is supported and give a reason for your conclusion. A. mean. B. is less than 1 standard deviation above the claimed is more than 4 standard deviations above the claimed mean. C. claimed mean. is less than 1 standard deviation above the D. is more than 4 standard deviations above the claimed mean. Question 9 of 40 2.5 Points In 1990, the average duration of long-distance telephone calls originating in one town was 9.3 minutes. A long-distance telephone company wants to perform a hypothesis test to determine whether the average duration of long-distance phone calls has changed from the 1990 mean of 9.3 minutes. Formulate the null and alternative hypotheses for the study described. A. Ho: = 9.3 minutes H a : < 9.3 minutes B. Ho: = 9.3 minutes H a : > 9.3 minutes C. Ho: = 9.3 minutes H a : 9.3 minutes D. Ho: 9.3 minutes H a : = 9.3 minutes Question 10 of 40 2.5 Points A psychologist claims that more than 19 percent of the population suffers from professional problems due to extreme shyness. Assume that a hypothesis test of the claim has been conducted and that the conclusion of the test was to reject the null hypothesis. Identify the population to which the results of the test apply. A. The population is all shy workers. B. The population cannot be identified from the description of the study. C. The population is all American workers. D. The population is all American professional workers (doctors, lawyers, CPA's, and the like.. Question 14 of 40 2.5 Points A researcher claims that the amounts of acetaminophen in a certain brand of cold tablets have a mean different from the 600 mg claimed by the manufacturer. Test this claim at the 0.02 level of significance. The mean acetaminophen content for a random sample of n = 41 tablets is 603.3 mg. Assume that the population standard deviation is 4.9 mg. A. Since the test statistic is greater than the critical z, there is sufficient evidence to accept the null hypothesis and to support the claim that the mean content of acetaminophen is 600 mg. B. Since the test statistic is greater than the critical z, there is sufficient evidence to reject the null hypothesis and to support the claim that the mean content of acetaminophen is not 600 mg. C. Since the test statistic is less than the critical z, there is sufficient evidence to reject the null hypothesis and to support the claim that the mean content of acetaminophen is not 600 mg. D. Since the test statistic is greater than the critical z, there is insufficient evidence to reject the null hypothesis and to support the claim that the mean content of acetaminophen is not 600 mg. Question 15 of 40 2.5 Points A skeptical paranormal researcher claims that the proportion of Americans that have seen a UFO is less than 1 in every one thousand. State the null hypothesis and the alternative hypothesis for a test of significance. A. H0: p = 0.001 Ha: p > 0.001 B. H0: p = 0.001 Ha: p < 0.001 C. H0: p > 0.001 Ha: p = 0.001 D. H0: p < 0.001 Ha: p = 0.001 Question 16 of 40 2.5 Points In 1990, the average duration of long-distance telephone calls originating in one town was 9.4 minutes. A long-distance telephone company wants to perform a hypothesis test to determine whether the average duration of long-distance phone calls has changed from the 1990 mean of 9.4 minutes. The mean duration for a random sample of 50 calls originating in the town was 8.6 minutes. Does the data provide sufficient evidence to conclude that the mean call duration, , is different from the 1990 mean of 9.4 minutes? Perform the appropriate hypothesis test using a significance level of 0.01. Assume that s= 4.8 minutes. A. With a z of -1.2 there is sufficient evidence to conclude that the mean value has changed from the 1990 mean of 9.4 minutes. B. With a P-value of 0.2302 there is not sufficient evidence to conclude that the mean value is less than the 1990 mean of 9.4 minutes. C. With a P-value of 0.2302 there is sufficient evidence to conclude that the mean value is less than the 1990 mean of 9.4 minutes. D. With a z of -1.2 there is not sufficient evidence to conclude that the mean value has changed from the 1990 mean of 9.4 minutes. Question 17 of 40 2.5 Points In the past, the mean running time for a certain type of flashlight battery has been 8.0 hours. The manufacturer has introduced a change in the production method and wants to perform a hypothesis test to determine whether the mean running time has increased as a result. The hypotheses are: H0 : = 8.0 hours Ha : > 8.0 hours Explain the meaning of a Type II error. A. Concluding that > 8.0 hours when in fact > 8.0 hours B. Failing to reject the hypothesis that = 8.0 hours when in fact > 8.0 hours C. Concluding that > 8.0 hours D. Failing to reject the hypothesis that = 8.0 hours when in fact = 8.0 hours Question 19 of 40 2.5 Points A two-tailed test is conducted at the 0.10 significance level. What is the P-value required to reject the null hypothesis? A. Greater than or equal to .010 B. Greater than or equal to 0.05 C. Less than or equal to 0.10 D. Less than or equal to 0.05 Q 21 of 40 A golfer wished to find a ball that would travel more than 170 yards when hit with his 6-iron with a club head speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 12 times at the required speed. State the null and alternative hypotheses for this test. A. H0: > 170; Ha: = 170 B. H0: < 170; Ha: = 170 C. H0: = 170; Ha: > 170 D. H0: = 160; Ha: > 160 Question 22 of 40 2.5 Points The following data were analyzed using one-way analysis of variance. A B C 34 27 19 26 23 21 31 29 22 28 21 12 Which one of the following statements is correct? A. The purpose of the analysis is to determine whether the groups A, B, and C are independent. B. The purpose of the analysis is to test the hypothesis that the population means of the three groups are equal. C. The purpose of the analysis is to test the hypothesis that the population variances of the three groups are equal. D. The purpose of the analysis is to test the hypothesis that the sample means of the three groups are equal. Reset Selection Question 23 of 40 2.5 Points A golfer wished to find a ball that would travel more than 160 yards when hit with his 7-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 8 times at the required speed. Data from this test resulted in a sample mean of 163.2 yards with a sample standard deviation of 5.8 yards. Assuming normality, carry out a hypothesis test at the 0.05 significance level to determine whether the ball meets the golfer's requirements. Use the partial t-table below to solve this problem. Area in one tail A. Do not reject the null hypothesis. The data do not provide sufficient evidence that the average distance is greater than 160 yards. B. Reject the null hypothesis. The data does provide sufficient evidence that the average distance is greater than 160 yards. C. t= 1.2334; Critical value = 1.992 D. Insufficient information to answer this question. Reset Selection Table 1 Degrees of Freedom n-1 6 7 8 9 Area in one tail 0.025 0.05 Area in two tails 0.05 0.10 2.447 2.365 2.306 2.262 1.943 1.895 1.860 1.833 Question 24 of 40 2.5 Points Which of the following statements is true? A. The distribution can be used when finding a confidence interval for the population mean whenever the sample size is small. B. The p distribution can be used when finding a confidence interval for the population mean whenever the sample size is small. C. The t distribution cannot be used when finding a confidence interval for the population mean whenever the sample size is small. D. The p distribution cannot be used when finding a confidence interval for the sample mean whenever the sample size is small. Reset Selection Question 25 of 40 2.5 Points A 95% confidence interval for the mean of a normal population is found to be 15.6 < < 25.2. What is the margin of error? A. 3.9 B. 4.8 C. 4.9 D. 3.7 Reset Selection Question 26 of 40 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The critical value of X2 for a 2 x 2 table using a 0.05 significance level is 3.841. If the value of the X2 statistic is 3.427, state your conclusion about the relationship between gender and colorblindness. A. Do not reject H0. There is not sufficient evidence to support the claim that gender and colorblindness are related. B. Do not reject H0. There is sufficient evidence to support the claim that gender and colorblindness are related. C. Reject H0. There is not sufficient evidence to support the claim that gender and colorblindness are related. D. Reject H0. There is sufficient evidence to support the claim that gender and colorblindness are related. Reset Selection Question 27 of 40 2.5 Points Which of the following statements is true? A. The t distribution cannot be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population. B. The t distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population. C. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population. D. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population. Reset Selection Question 28 of 40 2.5 Points A golfer wished to find a ball that would travel more than 180 yards when hit with his 5-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 7 times at the required speed. Data from this test resulted in a sample mean of 184.2 yards and a sample standard deviation of 5.8 yards. Assuming normality, carry out a hypothesis test at the 0.05 significance level to determine whether the ball meets the golfer's requirements. Use the partial t-table below. A. Reject the null hypothesis. The data do not provide sufficient evidence that the average distance is greater than 180 yards. B. Reject the null hypothesis. The data do provide sufficient evidence that the average distance is greater than 180 yards. Table 11 Degrees of Freedom n-1 6 7 8 9 Area in one tail 0.025 0.05 Area in two tails 0.05 0.10 2.447 2.365 2.306 2.262 1.943 1.895 1.860 1.833 C. Do not reject the null hypothesis. The data do provide sufficient evidence that the average distance is greater than 180 yards. D. Do not reject the null hypothesis. The data do not provide sufficient evidence that the average distance is greater than 180 yards. Question 30 of 40 2.5 Points Which of the following statements is true? A. The p distribution cannot be used when finding a confidence interval for the population mean with a small sample anytime the population standard deviation is unknown. B. The t distribution can be used when finding a confidence interval for the population mean with a small sample anytime the population standard deviation is unknown. C. The t distribution cannot be used when finding a confidence interval for the population mean with a small sample anytime the population standard deviation is unknown. D. The p distribution can be used when finding a confidence interval for the population mean with a small sample anytime the population standard deviation is unknown. Reset Selection Question 31 of 40 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The following counts were observed. If gender and colorblindness are independent, find the expected values corresponding to the four combinations of gender and colorblindness, and enter them in the following table along with row and column totals. A. Male Colorblind 6.0; Male Not Colorblind 54.0 B. Male Colorblind 7.0; Male Not Colorblind 53.0 C. Male Colorblind 8.0; Male Not Colorblind 52.0 D. Male Colorblind 6.0; Male Not Colorblind 53.0 Question 32 of 40 2.5 Points Table 12 Colorblind Male Female Total Not Colorblind 8 52 2 38 10 90 Total 60 40 100 A golfer wished to find a ball that would travel more than 180 yards when hit with his 5-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 7 times at the required speed. State the null and alterTable 13 Colorblind Not Colorblind Total Male Female Total native hypotheses for this test. A. H0: = 180; Ha: > 180 B. H0: > 180; Ha: > 180 C. H0: < 180; Ha: > 180 D. H0: = 180; Ha: < 180 A golfer wished to find a ball that would travel more than 170 yards when hit with his 6-iron with a club head speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 12 times at the required speed. Data from this test had a sample mean of 171.6 yards with a sample standard deviation of 2.4 yards. Assuming normality, carry out a hypothesis test at the 0.05 significance level to determine whether the ball meets the golfer's requirements. Use the partial t-table below. A. Accept the null hypothesis. The data do not provide sufficient evidence that the average dis tance is greater than 170 yards. B. Accept the null hypothesis. The data do provide sufficient evidence that the average distance is greater than 170 yards. C. Reject the null hypothesis. The data do not provide sufficient evidence that the average distance is greater than 170 yards. D. Reject the null hypothesis. The data do provide sufficient evidence that the average distance is greater than 170 yards. Reset Selection Table 14 Degrees of Freedom n-1 6 7 8 9 Area in one tail 0.025 0.05 Area in two tails 0.05 0.10 2.447 2.365 2.306 2.262 1.943 1.895 1.860 1.833 Question 35 of 40 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The following counts were observed. If gender and colorblindness are independent, find the expected values corresponding to the male combinations of gender and colorblindness. A. Colorblind Male 4.8; Not Colorblind Male 55.2 B. Colorblind Male 6.8; Not Colorblind Male 53.2 C. Colorblind Male 4.8; Not Colorblind Male 55.4 D. Colorblind Male 4.8; Not Colorblind Male 56.2 Table 15 Colorblind Male Female Total Not Colorblind 7 53 1 39 8 92 Question 36 of 40 2.5 Points A golfer wished to find a ball that would travel more than 160 yards when hit with his 7-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 8 times at the required speed. State the null and alternative hypotheses for this test. A. H0: = 160; Ha: > 150 B. H0: = 150; Ha: > 150 C. H0: = 160; Ha: > 160 D. H0: = 140; Ha: > 160 Question 37 of 40 2.5 Points A large test statistic F tells us that the sample means __________ the data within the individual samples, which would be unlikely if the populations means really were equal (as the null hypothesis claims). A. differ more than B. differ less than C. are equal to D. do not vary with Reset Selection Question 38 of 40 2.5 Points The margin of error in estimating the population mean of a normal population is E = 9.3 when the sample size is 15. If the sample size had been 25 and the sample standard deviation did not change, would the margin of error be larger or smaller than 9.3? A. Smaller. E increases as the square root of the sample size gets larger. B. Smaller. E decreases as the square root of the sample size gets larger. C. Larger. E decreases as the square root of the sample size gets larger. D. Larger. E increases as the square root of the sample size gets larger. Reset Selection Question 40 of 40 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The critical value of X2 for a 2 x 2 table using a 0.05 significance level is 3.841. If the value of the X2 statistic is 3.179, state your conclusion about the relationship between gender and colorblindness. A. Do not reject H0. B. Reject H0. C. There is sufficient evidence to support the claim that gender and colorblindness are not related. D. There is not sufficient evidence to accept or reject H0. 30.0/ 50.0 Points Question 1 of 40 0.0/ 2.5 Points A researcher wants to check the claim that convicted burglars spend an average of 18.7 months in jail. She takes a random sample of 35 such cases from court les and nds that months. Assume that the population standard deviation is 7 months. Test the null hypothesis that = 18.7 at the 0.05 signicance level. A. Do not reject the null hypothesis and conclude that the claim that the mean is dierent from 18.7 months is supported. B. Do not reject the null hypothesis and conclude that the claim that the mean is dierent from 18.7 months cannot be supported. C. Reject the null hypothesis and conclude that the claim that the mean is dierent from 18.7 months is supported. D. Reject the null hypothesis and conclude that the claim that the mean is dierent from 18.7 months cannot be supported. Question 2 of 40 0.0/ 2.5 Points A two-tailed test is conducted at the 5% signicance level. What is the left tail percentile required to reject the null hypothesis? A. 97.5% B. 5% C. 2.5% D. 95% Question 3 of 40 2.5/ 2.5 Points At one school, the mean amount of time that tenth-graders spend watching television each week is 18.4 hours. The principal introduces a campaign to encourage the students to watch less television. One year later, the principal wants to perform a hypothesis test to determine whether the average amount of time spent watching television per week has decreased. Formulate the null and alternative hypotheses for the study described. A. Ho: = 18.4 hours H a : 18.4 hours B. Ho: = 18.4 hours H a : < 18.4 hours C. Ho: 18.4 hours H a : < 18.4 hours D. Ho: = 18.4 hours H a : > 18.4 hours Question 4 of 40 2.5/ 2.5 Points A consumer group claims that the mean running time for a certain type of ashlight battery is not the same as the manufacturer's claims. Determine the null and alternative hypotheses for the test described. A. H0: = Manufacturer's claims Ha: < Manufacturer's claims B. H0: = Manufacturer's claims Ha: Manufacturer's claims C. H0: = Manufacturer's claims Ha: > Manufacturer's claims D. H0: Manufacturer's claims Ha: = Manufacturer's claims Question 5 of 40 2.5/ 2.5 Points The owner of a football team claims that the average attendance at home games is over 3000, and he is therefore justied 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 non-technical terms. A. There is sucient evidence to support the claim that the mean attendance is greater than 3000. B. There is sucient evidence to support the claim that the mean attendance is equal to 3000. C. There is not sucient evidence to support the claim that the mean attendance is greater than 3000. D. There is not sucient evidence to support the claim that the mean attendance is less than 3000. Question 6 of 40 0.0/ 2.5 Points If a fan purchased a bag with 30 peanuts, what is the lowest level at which this would be a signicant event? A. 0.05 B. 0.025 C. 0.01 D. It is not signicant at any of the levels given Question 7 of 40 0.0/ 2.5 Points In the past, the mean running time for a certain type of ashlight battery has been 9.8 hours. The manufacturer has introduced a change in the production method and wants to perform a hypothesis test to determine whether the mean running time has increased as a result. The hypotheses are: H0 : = 9.8 hours Ha : > 9.8 hours Suppose that the results of the sampling lead to rejection of the null hypothesis. Classify that conclusion as a Type I error, a Type II error, or a correct decision, if in fact the mean running time has not increased. A. Type I error B. Type II error C. Correct decision D. Can not be determined from this information Question 8 of 40 0.0/ 2.5 Points without computing a P-value, determine whether the alternate hypothesis is supported and give a reason for your conclusion. A. is less than 1 standard deviation above the claimed mean. B. mean. is more than 4 standard deviations above the claimed C. mean. is less than 1 standard deviation above the claimed D. is more than 4 standard deviations above the claimed mean. Question 9 of 40 2.5/ 2.5 Points In 1990, the average duration of long-distance telephone calls originating in one town was 9.3 minutes. A long-distance telephone company wants to perform a hypothesis test to determine whether the average duration of long-distance phone calls has changed from the 1990 mean of 9.3 minutes. Formulate the null and alternative hypotheses for the study described. A. Ho: = 9.3 minutes H a : < 9.3 minutes B. Ho: = 9.3 minutes H a : > 9.3 minutes C. Ho: = 9.3 minutes H a : 9.3 minutes D. Ho: 9.3 minutes H a : = 9.3 minutes Question 10 of 40 0.0/ 2.5 Points A psychologist claims that more than 19 percent of the population suers from professional problems due to extreme shyness. Assume that a hypothesis test of the claim has been conducted and that the conclusion of the test was to reject the null hypothesis. Identify the population to which the results of the test apply. A. The population is all shy workers. B. The population cannot be identied from the description of the study. C. The population is all American workers. D. The population is all American professional workers (doctors, lawyers, CPA's, and the like.. Question 11 of 40 2.5/ 2.5 Points A consumer advocacy group claims that the mean amount of juice in a 16 ounce bottled drink is not 16 ounces, as stated by the bottler. Determine the null and alternative hypotheses for the test described. A. H0: = 16 ounces Ha: < 16 ounces B. H0: 16 ounces Ha: = 16 ounces C. H0: = 16 ounces Ha: > 16 ounces D. H0: = 16 ounces Ha: 16 ounces Question 12 of 40 2.5/ 2.5 Points A two-tailed test is conducted at the 5% signicance level. What is the P-value required to reject the null hypothesis? A. Greater than or equal to 0.10 B. Less than or equal to 0.05 C. Less than or equal to 0.10 D. Greater than or equal to 0.05 Question 13 of 40 2.5/ 2.5 Points A long-distance telephone company claims that the mean duration of longdistance telephone calls originating in one town was greater than 9.4 minutes, which is the average for the state. Determine the conclusion of the hypothesis test assuming that the results of the sampling do not lead to rejection of the null hypothesis. A. Conclusion: Support the claim that the mean is less than 9.4 minutes. B. Conclusion: Support the claim that the mean is greater than 9.4 minutes. C. Conclusion: Support the claim that the mean is equal to 9.4 minutes. D. Conclusion: Do not support the claim that the mean is greater than 9.4 minutes. Question 14 of 40 0.0/ 2.5 Points A researcher claims that the amounts of acetaminophen in a certain brand of cold tablets have a mean dierent from the 600 mg claimed by the manufacturer. Test this claim at the 0.02 level of signicance. The mean acetaminophen content for a random sample of n = 41 tablets is 603.3 mg. Assume that the population standard deviation is 4.9 mg. A. Since the test statistic is greater than the critical z, there is sucient evidence to accept the null hypothesis and to support the claim that the mean content of acetaminophen is 600 mg. B. Since the test statistic is greater than the critical z, there is sucient evidence to reject the null hypothesis and to support the claim that the mean content of acetaminophen is not 600 mg. C. Since the test statistic is less than the critical z, there is sucient evidence to reject the null hypothesis and to support the claim that the mean content of acetaminophen is not 600 mg. D. Since the test statistic is greater than the critical z, there is insucient evidence to reject the null hypothesis and to support the claim that the mean content of acetaminophen is not 600 mg. Question 15 of 40 2.5/ 2.5 Points A skeptical paranormal researcher claims that the proportion of Americans that have seen a UFO is less than 1 in every one thousand. State the null hypothesis and the alternative hypothesis for a test of signicance. A. H0: p = 0.001 Ha: p > 0.001 B. H0: p = 0.001 Ha: p < 0.001 C. H0: p > 0.001 Ha: p = 0.001 D. H0: p < 0.001 Ha: p = 0.001 Question 16 of 40 2.5/ 2.5 Points In 1990, the average duration of long-distance telephone calls originating in one town was 9.4 minutes. A long-distance telephone company wants to perform a hypothesis test to determine whether the average duration of long-distance phone calls has changed from the 1990 mean of 9.4 minutes. The mean duration for a random sample of 50 calls originating in the town was 8.6 minutes. Does the data provide sucient evidence to conclude that the mean call duration, , is dierent from the 1990 mean of 9.4 minutes? Perform the appropriate hypothesis test using a signicance level of 0.01. Assume that s = 4.8 minutes. A. With a z of -1.2 there is sucient evidence to conclude that the mean value has changed from the 1990 mean of 9.4 minutes. B. With a P-value of 0.2302 there is not sucient evidence to conclude that the mean value is less than the 1990 mean of 9.4 minutes. C. With a P-value of 0.2302 there is sucient evidence to conclude that the mean value is less than the 1990 mean of 9.4 minutes. D. With a z of -1.2 there is not sucient evidence to conclude that the mean value has changed from the 1990 mean of 9.4 minutes. Question 17 of 40 2.5/ 2.5 Points In the past, the mean running time for a certain type of ashlight battery has been 8.0 hours. The manufacturer has introduced a change in the production method and wants to perform a hypothesis test to determine whether the mean running time has increased as a result. The hypotheses are: H0 : = 8.0 hours Ha : > 8.0 hours Explain the meaning of a Type II error. A. Concluding that > 8.0 hours when in fact > 8.0 hours B. Failing to reject the hypothesis that = 8.0 hours when in fact > 8.0 hours C. Concluding that > 8.0 hours D. Failing to reject the hypothesis that = 8.0 hours when in fact = 8.0 hours Question 18 of 40 2.5/ 2.5 Points The owner of a football team claims that the average attendance at home games is over 4000, and he is therefore justied in moving the team to a city with a larger stadium. Assume that a hypothesis test of the claim has been conducted and that the conclusion of the test was to reject the null hypothesis. Identify the population to which the results of the test apply. A. All games played by the team in question in which the attendance is over 4000 B. All future home games to be played by the team in question C. All home games played by the team in question D. None of the populations given are appropriate Question 19 of 40 0.0/ 2.5 Points A two-tailed test is conducted at the 0.10 signicance level. What is the P-value required to reject the null hypothesis? A. Greater than or equal to .010 B. Greater than or equal to 0.05 C. Less than or equal to 0.10 D. Less than or equal to 0.05 Question 20 of 40 2.5/ 2.5 Points z = 1.8 for Ha: > claimed value. What is the P-value for the test? A. 0.9641 B. 3.59 C. 96.41 D. 0.0359 Part 2 of 2 30.0/ 50.0 Points Question 21 of 40 2.5/ 2.5 Points A golfer wished to nd a ball that would travel more than 170 yards when hit with his 6-iron with a club head speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 12 times at the required speed. State the null and alternative hypotheses for this test. A. H0: > 170; Ha: = 170 B. H0: < 170; Ha: = 170 C. H0: = 170; Ha: > 170 D. H0: = 160; Ha: > 160 Question 22 of 40 2.5/ 2.5 Points The following data were analyzed using one-way analysis of variance. A B C 34 27 19 26 23 21 31 29 22 28 21 12 Which one of the following statements is correct? A. The purpose of the analysis is to determine whether the groups A, B, and C are independent. B. The purpose of the analysis is to test the hypothesis that the population means of the three groups are equal. C. The purpose of the analysis is to test the hypothesis that the population variances of the three groups are equal. D. The purpose of the analysis is to test the hypothesis that the sample means of the three groups are equal. Question 23 of 40 2.5/ 2.5 Points A golfer wished to nd a ball that would travel more than 160 yards when hit with his 7-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 8 times at the required speed. Data from this test resulted in a sample mean of 163.2 yards with a sample standard deviation of 5.8 yards. Assuming normality, carry out a hypothesis test at the 0.05 signicance level to determine whether the ball meets the golfer's requirements. Use the partial t-table below to solve this problem. Area in one tail 0.025 0.05 Area in two tails Degrees of Freedom n - 1 0.05 0.10 6 2.447 1.943 7 2.365 1.895 8 2.306 1.860 9 2.262 1.833 A. Do not reject the null hypothesis. The data do not provide sucient evidence that the average distance is greater than 160 yards. B. Reject the null hypothesis. The data does provide sucient evidence that the average distance is greater than 160 yards. C. t= 1.2334; Critical value = 1.992 D. Insucient information to answer this question. Question 24 of 40 0.0/ 2.5 Points Which of the following statements is true? A. The t distribution can be used when nding a condence interval for the population mean whenever the sample size is small. B. The p distribution can be used when nding a condence interval for the population mean whenever the sample size is small. C. The t distribution cannot be used when nding a condence interval for the population mean whenever the sample size is small. D. The p distribution cannot be used when nding a condence interval for the sample mean whenever the sample size is small. Question 25 of 40 2.5/ 2.5 Points A 95% condence interval for the mean of a normal population is found to be 15.6 < < 25.2. What is the margin of error? A. 3.9 B. 4.8 C. 4.9 D. 3.7 Question 26 of 40 0.0/ 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The critical value of X2 for a 2 x 2 table using a 0.05 signicance level is 3.841. If the value of the X2 statistic is 3.427, state your conclusion about the relationship between gender and colorblindness. A. Do not reject H0. There is not sucient evidence to support the claim that gender and colorblindness are related. B. Do not reject H0. There is sucient evidence to support the claim that gender and colorblindness are related. C. Reject H0. There is not sucient evidence to support the claim that gender and colorblindness are related. D. Reject H0. There is sucient evidence to support the claim that gender and colorblindness are related. Question 27 of 40 0.0/ 2.5 Points Which of the following statements is true? A. The t distribution cannot be used when nding a condence interval for the population mean with a small sample whenever the sample comes from a symmetric population. B. The t distribution can be used when nding a condence interval for the population mean with a small sample whenever the sample comes from a symmetric population. C. The p distribution can be used when nding a condence interval for the population mean with a small sample whenever the sample comes from a symmetric population. D. The p distribution can be used when nding a condence interval for the population mean with a small sample whenever the sample comes from a symmetric population. Question 28 of 40 2.5/ 2.5 Points A golfer wished to nd a ball that would travel more than 180 yards when hit with his 5-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 7 times at the required speed. Data from this test resulted in a sample mean of 184.2 yards and a sample standard deviation of 5.8 yards. Assuming normality, carry out a hypothesis test at the 0.05 signicance level to determine whether the ball meets the golfer's requirements. Use the partial t-table below. Area in one tail 0.025 0.05 Area in two tails Degrees of Freedom n - 1 0.05 0.10 6 2.447 1.943 7 2.365 1.895 8 2.306 1.860 9 2.262 1.833 A. Reject the null hypothesis. The data do not provide sucient evidence that the average distance is greater than 180 yards. B. Reject the null hypothesis. The data do provide sucient evidence that the average distance is greater than 180 yards. C. Do not reject the null hypothesis. The data do provide sucient evidence that the average distance is greater than 180 yards. D. Do not reject the null hypothesis. The data do not provide sucient evidence that the average distance is greater than 180 yards. Question 29 of 40 2.5/ 2.5 Points A 95% condence interval for the mean of a normal population is found to be 17.6 < < 23.6. What is the margin of error? A. 2.0 B. 2.7 C. 3.0 D. 4.0 Question 30 of 40 0.0/ 2.5 Points Which of the following statements is true? A. The p distribution cannot be used when nding a condence interval for the population mean with a small sample anytime the population standard deviation is unknown. B. The t distribution can be used when nding a condence interval for the population mean with a small sample anytime the population standard deviation is unknown. C. The t distribution cannot be used when nding a condence interval for the population mean with a small sample anytime the population standard deviation is unknown. D. The p distribution can be used when nding a condence interval for the population mean with a small sample anytime the population standard deviation is unknown. Question 31 of 40 0.0/ 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The following counts were observed. Colorblind Not Colorblind Total Male 8 52 60 Female 2 38 40 Total 10 90 100 If gender and colorblindness are independent, nd the expected values corresponding to the four combinations of gender and colorblindness, and enter them in the following table along with row and column totals. Colorblind Not Colorblind Total Male Female Total A. Male Colorblind 6.0; Male Not Colorblind 54.0 B. Male Colorblind 7.0; Male Not Colorblind 53.0 C. Male Colorblind 8.0; Male Not Colorblind 52.0 D. Male Colorblind 6.0; Male Not Colorblind 53.0 Question 32 of 40 2.5/ 2.5 Points A golfer wished to nd a ball that would travel more than 180 yards when hit with his 5-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 7 times at the required speed. State the null and alternative hypotheses for this test. A. H0: = 180; Ha: > 180 B. H0: > 180; Ha: > 180 C. H0: < 180; Ha: > 180 D. H0: = 180; Ha: < 180 Question 33 of 40 2.5/ 2.5 Points A golfer wished to nd a ball that would travel more than 170 yards when hit with his 6-iron with a club head speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 12 times at the required speed. Data from this test had a sample mean of 171.6 yards with a sample standard deviation of 2.4 yards. Assuming normality, carry out a hypothesis test at the 0.05 signicance level to determine whether the ball meets the golfer's requirements. Use the partial t-table below. Area in one tail 0.025 0.05 0.05 0.10 6 2.447 1.943 7 2.365 1.895 8 2.306 1.860 9 2.262 1.833 Area in two tails Degrees of Freedom n - 1 A. Accept the null hypothesis. The data do not provide sucient evidence that the average distance is greater than 170 yards. B. Accept the null hypothesis. The data do provide sucient evidence that the average distance is greater than 170 yards. C. Reject the null hypothesis. The data do not provide sucient evidence that the average distance is greater than 170 yards. D. Reject the null hypothesis. The data do provide sucient evidence that the average distance is greater than 170 yards. Question 34 of 40 2.5/ 2.5 Points The __________ test statistic is for the one-way analysis of variance. A. P-Value B. t C. F D. p Question 35 of 40 0.0/ 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The following counts were observed. Colorblind Not Colorblind Total Male 7 53 60 Female 1 39 40 Total 8 92 100 If gender and colorblindness are independent, nd the expected values corresponding to the male combinations of gender and colorblindness. A. Colorblind Male 4.8; Not Colorblind Male 55.2 B. Colorblind Male 6.8; Not Colorblind Male 53.2 C. Colorblind Male 4.8; Not Colorblind Male 55.4 D. Colorblind Male 4.8; Not Colorblind Male 56.2 Question 36 of 40 2.5/ 2.5 Points A golfer wished to nd a ball that would travel more than 160 yards when hit with his 7-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 8 times at the required speed. State the null and alternative hypotheses for this test. A. H0: = 160; Ha: > 150 B. H0: = 150; Ha: > 150 C. H0: = 160; Ha: > 160 D. H0: = 140; Ha: > 160 Question 37 of 40 2.5/ 2.5 Points A large test statistic F tells us that the sample means __________ the data within the individual samples, which would be unlikely if the populations means really were equal (as the null hypothesis claims). A. dier more than B. dier less than C. are equal to D. do not vary with Question 38 of 40 2.5/ 2.5 Points The margin of error in estimating the population mean of a normal population is E = 9.3 when the sample size is 15. If the sample size had been 25 and the sample standard deviation did not change, would the margin of error be larger or smaller than 9.3? A. Smaller. E increases as the square root of the sample size gets larger. B. Smaller. E decreases as the square root of the sample size gets larger. C. Larger. E decreases as the square root of the sample size gets larger. D. Larger. E increases as the square root of the sample size gets larger. Question 39 of 40 0.0/ 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The critical value of X2 for a 2 x 2 table using a 0.05 signicance level is 3.841. If the value of the X2 statistic is 4.613, state your conclusion about the relationship between gender and colorblindness. A. Reject H0. There is not sucient evidence to support the claim that gender and colorblindness are related. B. Reject H0. There is sucient evidence to support the claim that gender and colorblindness are related. C. Do not Reject H0. There is sucient evidence to support the claim that gender and colorblindness are related. D. Do not Reject H0. There is not sucient evidence to support the claim that gender and colorblindness are related. Question 40 of 40 0.0/ 2.5 Points One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The critical value of X2 for a 2 x 2 table using a 0.05 signicance level is 3.841. If the value of the X2 statistic is 3.179, state your conclusion about the relationship between gender and colorblindness. A. Do not reject H0. B. Reject H0. C. There is sucient evidence to support the claim that gender and colorblindness are not related. D. There is not sucient evidence to accept or reject H0. 1. special case: linear + no question to answer 2. normal ow