## Business Statistics

Statistics

## Quiz 9 :

Statistical Inference: Hypothesis Testing for Single Populations

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Q29 Q29 Q29

If car manufacturer of cars orders the windshields from another company.The width of the windshields received need to be within 0.2 mm of the average width.The contract between the car manufacturer and the windshield suppler should include a clause related to the delivered windshields' median.

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Q38 Q38 Q38

Suppose that H

_{o}: 0.01 H_{a}: > 0.01 The value 0.01 is the maximum safe level of some naturally occurring lethal pollutant in drinking water for human consumption.You need to decide if you will use water coming from a specific source for one of the beverages your company produces, based on sample measures of this pollutant taken in random different locations and times at the source of water.In this case you would want toFree

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Multiple Choice

Q41 Q41 Q41

The customer help center in your company receives calls from customers who need help with some of the customized software solutions your company provides.Your company claims that the average waiting time is 7 minutes at the busiest time, from 8 a.m.to 10 a.m., Monday through Thursday.One of your main clients has recently complained that every time she calls during the busy hours, the waiting time exceeds 7 minutes.You conduct a statistical study to determine the average waiting time with a sample of 35 calls for which you obtain an average waiting time of 8.15 minutes.If the population standard deviation is known to be 4.2 minutes, and α = 0.05, the p-value is approximately

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Q42 Q42 Q42

The customer help center in your company receives calls from customers who need help with some of the customized software solutions your company provides.Your company claims that the average waiting time is 7 minutes at the busiest time, from 8 a.m.to 10 a.m., Monday through Thursday.One of your main clients has recently complained that every time she calls during the busy hours, the waiting time exceeds 7 minutes.You conduct a statistical study to determine the average waiting time with a sample of 35 calls for which you obtain an average waiting time of 8.15 minutes.If the population standard deviation is known to be 4.2 minutes, and α = 0.05, the appropriate decision is to ___________.

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Multiple Choice

Q48 Q48 Q48

Suppose you are testing the null hypothesis that a population mean is less than or equal to 46, against the alternative hypothesis that the population mean is greater than 46.If the sample size is 25, is known, and α = .01, the critical value of z is _______.

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Q49 Q49 Q49

Suppose you are testing the null hypothesis that a population mean is less than or equal to 46, against the alternative hypothesis that the population mean is greater than 46.The sample size is 25 and α =.05.If the sample mean is 50 and the population standard deviation is 8, the observed z value is _______.

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Q50 Q50 Q50

Suppose you are testing the null hypothesis that a population mean is greater than or equal to 60, against the alternative hypothesis that the population mean is less than 60.The sample size is 64 and = .05.If the sample mean is 58 and the population standard deviation is 16, the observed z value is _______.

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Multiple Choice

Q51 Q51 Q51

A researcher is testing a hypothesis of a single mean.The critical z value for = .05 in a one?tailed test is 1.645.The observed z value from sample data is 1.13.The decision made by the researcher based on this information is to ______ the null hypothesis.

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Q52 Q52 Q52

A researcher is testing a hypothesis of a single mean.The critical z value for = .05 in a two?tailed test is +1.96.The observed z value from sample data is ?1.85.The decision made by the researcher based on this information is to _____ the null hypothesis.

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Q54 Q54 Q54

A researcher is testing a hypothesis of a single mean.The critical z value for = .05 in a two?tailed test is +1.96.The observed z value from sample data is -2.11.The decision made by the researcher based on this information is to _____ the null hypothesis.

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Multiple Choice

Q55 Q55 Q55

A coffee-dispensing machine is supposed to deliver 8 ounces of liquid into each paper cup, but a consumer believes that the actual mean amount is less.The consumer obtained a sample of 49 cups of the dispensed liquid with average of 7.75 ounces.If the sample variance of the dispensed liquid per cup is 0.81 ounces, and α = 0.05, the p-value is approximately __________.

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Multiple Choice

Q56 Q56 Q56

A coffee-dispensing machine is supposed to deliver 8 ounces of liquid into each paper cup, but a consumer believes that the actual mean amount is less.The consumer obtained a sample of 49 cups of the dispensed liquid with average of 7.75 ounces.If the sample variance of the dispensed liquid delivered per cup is 0.81 ounces, and α = 0.05, the appropriate decision is to ________.

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Multiple Choice

Q57 Q57 Q57

The local swim team is considering offering a new semi-private class aimed at entry-level swimmers, but needs at minimum number of swimmers to sign up in order to be cost effective.Last year's data showed that during 8 swim sessions the average number of entry-level swimmers attending was 15.Suppose the instructor wants to conduct a hypothesis test.The alternative hypothesis for this hypothesis test is: "the population mean is less than 15".The sample size is 8, is known, and α =.05, the critical value of z is _______.

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Multiple Choice

Q58 Q58 Q58

The local swim team is considering offering a new semi-private class aimed at entry-level swimmers, but needs a minimum number of swimmers to sign up in order to be cost effective.Last year's data showed that during 8 swim sessions the average number of entry-level swimmers attending was 15.Suppose the instructor wants to conduct a hypothesis test and the alternative hypothesis is "the population mean is greater than 15." If the sample size is 5, is known, and α = .01, the critical value of z is _______.

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Q59 Q59 Q59

A home building company routinely orders standard interior doors with a height of 80 inches.Recently the installers have complained that the doors are not the standard height.The quality control inspector for the home building company is concerned that the manufacturer is supplying doors that are not 80 inches in height.In an effort to test this, the inspector is going to gather a sample of the recently received doors and measure the height.The alternative hypothesis for the statistical test to determine if the doors are not 80 inches is __________.

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Q60 Q60 Q60

Jennifer Cantu, VP of Customer Services at Tri-State Auto Insurance, Inc., monitors the claims processing time of the claims division.Her standard includes "a mean processing time of 5 days or less." Each week, her staff checks for compliance by analyzing a random sample of 60 claims.Jennifer's null hypothesis is ________.

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Multiple Choice

Q61 Q61 Q61

The customer help center in your company receives calls from customers who need help with some of the customized software solutions your company provides.Your company claims that the average waiting time is 7 minutes at the busiest time, from 8 a.m.to 10 a.m., Monday through Thursday.One of your main clients has recently complained that every time she calls during the busy hours, the waiting time exceeds 7 minutes.You conduct a statistical study to determine the average waiting time with a sample of 35 calls, for which you obtain an average waiting time of 8.15 minutes.Suppose that you can assume that waiting times are normally distributed.The sample standard deviation is 4.2 minutes.The null hypothesis is:

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Q62 Q62 Q62

In performing a hypothesis test where the null hypothesis is that the population mean is 23 against the alternative hypothesis that the population mean is not equal to 23, a random sample of 17 items is selected.The sample mean is 24.6 and the sample standard deviation is 3.3.It can be assumed that the population is normally distributed.The degrees of freedom associated with this are _______.

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Multiple Choice

Q63 Q63 Q63

In performing a hypothesis test where the null hypothesis is that the population mean is 4.8 against the alternative hypothesis that the population mean is not equal to 4.8, a random sample of 25 items is selected.The sample mean is 4.1 and the sample standard deviation is 1.4.It can be assumed that the population is normally distributed.The degrees of freedom associated with this are _______.

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Q64 Q64 Q64

In performing a hypothesis test where the null hypothesis is that the population mean is 4.8 against the alternative hypothesis that the population mean is not equal to 4.8, a random sample of 25 items is selected.The sample mean is 4.1 and the sample standard deviation is 1.4.It can be assumed that the population is normally distributed.The observed "t" value for this problem is _______.

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Multiple Choice

Q67 Q67 Q67

The local oil changing business is very busy on Saturday mornings and is considering expanding.A national study of similar businesses reported the mean number of customers waiting to have their oil changed on Saturday morning is 3.6.Suppose the local oil changing business owner, wants to perform a hypothesis test.The null hypothesis is the population mean is 3.6 and the alternative hypothesis that the population mean is not equal to 3.6.The owner takes a random sample of 16 Saturday mornings during the past year and determines the sample mean is 4.2 and the sample standard deviation is 1.4.It can be assumed that the population is normally distributed.The observed "t" value for this problem is _______.

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Multiple Choice

Q68 Q68 Q68

The local oil changing business is very busy on Saturday mornings and is considering expanding.A national study of similar businesses reported the mean number of customers waiting to have their oil changed on Saturday morning is 3.6.Suppose the local oil changing business owner, wants to perform a hypothesis test.The null hypothesis is the population mean is 3.6 and the alternative hypothesis that the population mean is not equal to 3.6.The owner takes a random sample of 16 Saturday mornings during the past year and determines the sample mean is 4.2 and the sample standard deviation is 1.4.It can be assumed that the population is normally distributed and the level of significance is 0.05.The critical value found in the "t" table for this problem is _______.

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Multiple Choice

Q69 Q69 Q69

The local oil changing business is very busy on Saturday mornings and is considering expanding.A national study of similar businesses reported the mean number of customers waiting to have their oil changed on Saturday morning is 3.6.Suppose the local oil changing business owner, wants to perform a hypothesis test.The null hypothesis is the population mean is 3.6 and the alternative hypothesis is the population mean is not equal to 3.6.The owner takes a random sample of 16 Saturday mornings during the past year and determines the sample mean is 4.2 and the sample standard deviation is 1.4.It can be assumed that the population is normally distributed.The level of significance is 0.05.The decision rule for this problem is to reject the null hypothesis if the observed "t" value is _______.

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Multiple Choice

Q70 Q70 Q70

A coffee-dispensing machine is supposed to deliver 8 ounces of liquid into each paper cup, but a consumer believes that the actual mean amount is less.The consumer obtained a sample of 16 cups of the dispensed liquid with sample mean of 7.75 ounces and sample variance of 0.81 ounces.If the dispensed liquid delivered per cup is normally distributed, the appropriate decision at α = 0.05 is to ___________.

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Multiple Choice

Q71 Q71 Q71

The weight of a USB flash drive is 30 grams and is normally distributed.Periodically, quality control inspectors at Dallas Flash Drives randomly select a sample of 17 USB flash drives.If the mean weight of the USB flash drives is too heavy or too light the machinery is shut down for adjustment; otherwise, the production process continues.The last sample showed a mean and standard deviation of 31.9 and 1.8 grams, respectively.Using = 0.10, the critical "t" values are _______.

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Multiple Choice

Q72 Q72 Q72

The weight of a USB flash drive is 30 grams and is normally distributed.Periodically, quality control inspectors at Dallas Flash Drives randomly select a sample of 17 USB flash drives.If the mean weight of the USB flash drives is too heavy or too light the machinery is shut down for adjustment; otherwise, the production process continues.The last sample showed a mean and standard deviation of 31.9 and 1.8 grams, respectively.The null hypothesis is ______.

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Multiple Choice

Q73 Q73 Q73

The weight of a USB flash drive is 30 grams and is normally distributed.Periodically, quality control inspectors at Dallas Flash Drives randomly select a sample of 17 USB flash drives.If the mean weight of the USB flash drives is too heavy or too light the machinery is shut down for adjustment; otherwise, the production process continues.The last sample showed a mean and standard deviation of 31.9 and 1.8 grams, respectively.Using = 0.10, the appropriate decision is to _______.

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Multiple Choice

Q74 Q74 Q74

The customer help center in your company receives calls from customers who need help with some of the customized software solutions your company provides.Previous studies had indicated that 20% of customers who call the help center are Hispanics whose native language is Spanish and therefore would prefer to talk to a Spanish-speaking representative.This figure coincides with the national proportion, as shown by multiple larger polls.You want to test the hypothesis that 20% of the callers would prefer to talk to a Spanish-speaking representative.You conduct a statistical study with a sample of 35 calls and find out that 11 of the callers would prefer a Spanish-speaking representative.The significance level for this test is 0.01.The value of the test statistic obtained is:

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Multiple Choice

Q75 Q75 Q75

A political scientist wants to prove that a candidate is currently carrying more than 60% of the vote in the state.She has her assistants randomly sample 200 eligible voters in the state by telephone and only 90 declare that they support her candidate.The observed z value for this problem is _______.

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Multiple Choice

Q76 Q76 Q76

A company believes that it controls more than 30% of the total market share for one of its products.To prove this belief, a random sample of 144 purchases of this product is contacted.It is found that 50 of the 144 purchases were of this company's brand.If a researcher wants to conduct a statistical test for this problem, the alternative hypothesis would be _______.

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Multiple Choice

Q77 Q77 Q77

A company believes that it controls more than 30% of the total market share for one of its products.To prove this belief, a random sample of 144 purchases of this product is contacted.It is found that 50 of the 144 purchases were of this company's brand.If a researcher wants to conduct a statistical test for this problem, the observed z value would be _______.

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Multiple Choice

Q78 Q78 Q78

A company believes that it controls more than 30% of the total market share for one of its products.To prove this belief, a random sample of 144 purchases of this product is contacted.It is found that 50 of the 144 purchases were of this company's brand.If a researcher wants to conduct a statistical test for this problem, the test would be _______.

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Multiple Choice

Q79 Q79 Q79

A small restaurant owner believes no more than 36% of his customers travel over 10 miles to his business.He is interested in expanding his customer base through marketing.However, he would like to test his hypothesis prior to investing money in a marketing initiative.He intends to use the following null and alternative hypotheses. H

_{o}: p 0.36 H_{a}: p > 0.36 These hypotheses _______________.Free

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Q80 Q80 Q80

A small restaurant owner believes at least 36 % of his customers would be willing to order take out service if it were available.He is interested in surveying his customer base.He intends to use the following null and alternative hypotheses. H

_{o}: p 0.36 H_{a}: p < 0.36 These hypotheses _______________.Free

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Q81 Q81 Q81

A small restaurant owner believes exactly 36 % of his customers come to the restaurant because of his daily half-price specials.He is interested in expanding his daily specials and increasing the price.However, he would like to test his hypothesis prior to expanding the daily special offerings.He intends to use the following null and alternative hypotheses. H

_{o}: p = 0.36 H_{a}: p 0.36 These hypotheses _______________.Free

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Multiple Choice

Q82 Q82 Q82

Ophelia O'Brien, VP of Consumer Credit of American First Banks (AFB), monitors the default rate on personal loans at the AFB member banks.One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans.Last Friday's sample contained 30 defaulted loans.Ophelia's null hypothesis is _______.

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Q83 Q83 Q83

Ophelia O'Brien, VP of Consumer Credit of American First Banks (AFB), monitors the default rate on personal loans at the AFB member banks.One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans.Last Friday's sample contained 30 defaulted loans.Using = 0.10, the critical z value is _______.

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Q84 Q84 Q84

Ophelia O'Brien, VP of Consumer Credit of American First Banks (AFB), monitors the default rate on personal loans at the AFB member banks.One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans.Last Friday's sample contained 30 defaulted loans.Using = 0.10, the observed z value is _______.

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Multiple Choice

Q85 Q85 Q85

Ophelia O'Brien, VP of Consumer Credit of American First Banks (AFB), monitors the default rate on personal loans at the AFB member banks.One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans.Last Friday's sample contained 30 defaulted loans.Using = 0.10, the appropriate decision is to _______.

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Multiple Choice

Q86 Q86 Q86

Ophelia O'Brien, VP of Consumer Credit of American First Banks (AFB), monitors the default rate on personal loans at the AFB member banks.One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans.Last Friday's sample contained 38 defaulted loans.Using = 0.10, the appropriate decision is to _______.

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Multiple Choice

Q87 Q87 Q87

The executives of CareFree Insurance, Inc.feel that "a majority of our employees perceive a participatory management style at CareFree." A random sample of 200 CareFree employees is selected to test this hypothesis at the 0.05 level of significance.Eighty employees rate the management as participatory.The null hypothesis is __________.

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Q88 Q88 Q88

The executives of CareFree Insurance, Inc.feel that "a majority of our employees perceive a participatory management style at CareFree." A random sample of 200 CareFree employees is selected to test this hypothesis at the 0.05 level of significance.Eighty employees rate the management as participatory.The appropriate decision is to __________.

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Q89 Q89 Q89

The executives of CareFree Insurance, Inc.feel that "a majority of our employees perceive a participatory management style at CareFree." A random sample of 200 CareFree employees is selected to test this hypothesis at the 0.05 level of significance.Ninety employees rate the management as participatory.The appropriate decision is to __________.

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Q90 Q90 Q90

Elwin Osbourne, CIO at GFS, Inc., suspects that at least 25% of e-mail messages sent by GFS employees are not business related.A random sample of 300 e-mail messages was selected to test this hypothesis at the 0.01 level of significance.Fifty-four of the messages were not business related.The null hypothesis is ____.

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Q91 Q91 Q91

Elwin Osbourne, CIO at GFS, Inc., suspects that at least 25% of e-mail messages sent by GFS employees are not business related.A random sample of 300 e-mail messages was selected to test this hypothesis at the 0.01 level of significance.Fifty-four of the messages were not business related.The appropriate decision is to _______.

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Q92 Q92 Q92

Elwin Osbourne, CIO at GFS, Inc., suspects that at least 25% of e-mail messages sent by GFS employees are not business related.A random sample of 300 e-mail messages was selected to test this hypothesis at the 0.01 level of significance.Sixty of the messages were not business related.The appropriate decision is to _______.

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Q93 Q93 Q93

Discrete Components, Inc.manufactures a line of electrical resistors.Presently, the carbon composition line is producing 100-ohm resistors.The population variance of these resistors "must not exceed 4" to conform to industry standards.Periodically, the quality control inspectors check for conformity by randomly selecting 10 resistors from the line, and calculating the sample variance.The last sample had a variance of 4.36.Assume that the population is normally distributed.Using = 0.05, the null hypothesis is _________________.

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Multiple Choice

Q94 Q94 Q94

Albert Miller, VP of Production of a company that produces components for auto braking systems is examining the diameter of a specialized electrical wire produced with newly acquired machines in a new production line.For safety reasons, it is important that the variance in the diameter doesn't exceed 0.15 inches.Albert knows that the variance of the other production lines is 0.15 and he wants to make sure the new machine also delivers products whose variance doesn't exceed the safety limit.His staff randomly selects a sample of 25 wires and find out that the standard deviation of the sample is 0.42 inches.Assume that wire diameters are normally distributed.Using = 0.10, the appropriate decision is ________.

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Q95 Q95 Q95

Discrete Components, Inc.manufactures a line of electrical resistors.Presently, the carbon composition line is producing 100-ohm resistors.The population variance of these resistors "must not exceed 4" to conform to industry standards.Periodically, the quality control inspectors check for conformity by randomly select 10 resistors from the line, and calculating the sample variance.The last sample had a variance of 4.36.Assume that the population is normally distributed.Using = 0.05, the critical value of chi-square is _________________.

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Q96 Q96 Q96

Discrete Components, Inc.manufactures a line of electrical resistors.Presently, the carbon composition line is producing 100-ohm resistors.The population variance of these resistors "must not exceed 4" to conform to industry standards.Periodically, the quality control inspectors check for conformity by randomly select 10 resistors from the line, and calculating the sample variance.The last sample had a variance of 4.36.Assume that the population is normally distributed.Using = 0.05, the observed value of chi-square is _________________.

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Multiple Choice

Q97 Q97 Q97

Discrete Components, Inc.manufactures a line of electrical resistors.Presently, the carbon composition line is producing 100-ohm resistors.The population variance of these resistors "must not exceed 4" to conform to industry standards.Periodically, the quality control inspectors check for conformity by randomly select 10 resistors from the line, and calculating the sample variance.The last sample had a variance of 4.36.Assume that the population is normally distributed.Using = 0.05, the appropriate decision is _________________.

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Multiple Choice

Q98 Q98 Q98

David Desreumaux, VP of Human Resources of American First Banks (AFB), is reviewing the employee training programs of AFB.Based on a recent census of personnel, David knows that the variance of teller training time in the southeast region is 8, and he wonders if the variance in the southwest region is the same number.His staff randomly selected personnel files for 15 tellers in the southwest region, and determined that their mean training time was 25 hours and that the standard deviation was 4 hours.Assume that teller training time is normally distributed.Using = 0.10, the null hypothesis is ________.

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Q99 Q99 Q99

David Desreumaux, VP of Human Resources of American First Banks (AFB), is reviewing the employee training programs of AFB.Based on a recent census of personnel, David knows that the variance of teller training time in the southeast region is 8, and he wonders if the variance in the southwest region is the same number.His staff randomly selected personnel files for 15 tellers in the southwest region, and determined that their mean training time was 25 hours and that the standard deviation was 4 hours.Assume that teller training time is normally distributed.Using = 0.10, the critical values of chi-square are ________.

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Q100 Q100 Q100

David Desreumaux, VP of Human Resources of American First Banks (AFB), is reviewing the employee training programs of AFB banks.Based on a recent census of personnel, David knows that the variance of teller training time in the southeast region is 8, and he wonders if the variance in the southwest region is the same number.His staff randomly selected personnel files for 15 tellers in the southwest region, and determined that their mean training time was 25 hours and that the standard deviation was 4 hours.Assume that teller training time is normally distributed.Using = 0.10, the observed value of chi-square is ________.

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Multiple Choice

Q101 Q101 Q101

David Desreumaux, VP of Human Resources of American First Banks (AFB), is reviewing the employee training programs of AFB.Based on a recent census of personnel, David knows that the variance of teller training time in the southeast region is 8, and he wonders if the variance in the southwest region is the same number.His staff randomly selected personnel files for 15 tellers in the southwest region, and determined that their mean training time was 25 hours and that the standard deviation was 4 hours.Assume that teller training time is normally distributed.Using = 0.10, the appropriate decision is ________.

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Multiple Choice

Q102 Q102 Q102

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a variance of 1.8 or less with an alpha of 0.05.The company randomly tests 20 of these batteries to ensure that they are meeting the requirements of the contract.What would be the null hypothesis each time the company conducts the test of the variances?

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Multiple Choice

Q103 Q103 Q103

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a variance of 1.8 or less with an alpha of 0.05.The company randomly tests 20 of these batteries to ensure that they are meeting the requirements of the contract.If the most recent test had a variance of 1.9, what would be the critical value of this chi-squared test?

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Multiple Choice

Q104 Q104 Q104

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a variance of 1.8 or less with an alpha of 0.05.The company randomly tests 20 of these batteries to ensure that they are meeting the requirements of the contract.If the most recent test had a variance of 1.9, what would be the observed chi-squared value?

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Multiple Choice

Q105 Q105 Q105

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a variance of 1.8 or less with an alpha of 0.05.The company randomly tests 20 of these batteries to ensure that they are meeting the requirements of the contract.If the most recent test had a variance of 1.9, what should the company do?

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Q106 Q106 Q106

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a standard deviation of 1.5 or less with an alpha of 0.10.The company randomly tests 25 of these batteries to ensure that they are meeting the requirements of the contract.If the most recent test had a standard deviation of 1.8 what would be the critical value of this chi-squared test?

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Multiple Choice

Q107 Q107 Q107

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a standard deviation of 1.5 or less with an alpha of 0.10.The company randomly tests 25 of these batteries to ensure that they are meeting the requirements of the contract.If the most recent test had a standard deviation of 1.8 what would be the observed chi-squared value?

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Q108 Q108 Q108

A company has a contract to supply specialized batteries to a manufacturer with a mean width of 54mm and a standard deviation of 1.5 or less with an alpha of 0.10.The company randomly tests 25 of these batteries to ensure that they are meeting the requirements of the contract.If the most recent test had a standard deviation of 1.8, what should the company do?

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Q109 Q109 Q109

The lifetime of a squirrel follows a normal distribution with mean μ months and a standard deviation =7 months.To test the alternative hypothesis that μ > 40, 25 squirrels are randomly selected.The null hypothesis is rejected when the sample mean is bigger than 43.Assuming that μ=45, the probability of type II error is approximately _________.

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Q110 Q110 Q110

The lifetime of a squirrel follows a normal distribution with mean μ = 40 months and a standard deviation = 7 months.To test the hypothesis that μ > 40, 25 squirrels are randomly selected.Assuming that μ = 45, and α = 0.1, the probability of type II error is approximately

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Q112 Q112 Q112

A laptop battery lifespan follows a normal distribution with mean μ = 22 months and a standard deviation = 6 months.To test the alternative hypothesis that μ < 22 with α = .05, 36 laptop batteries are randomly selected.Assuming that μ = 21, the probability of type II error is approximately ________.

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Q113 Q113 Q113

A laptop battery lifespan follows a normal distribution with mean μ = 22 months and a standard deviation = 6 months.To test the alternative hypothesis that μ < 22 with α = .01, 36 laptop batteries are randomly selected.Assuming that μ = 24, the probability of type II error is approximately ________.

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Q114 Q114 Q114

A laptop battery lifespan follows a normal distribution with mean μ = 20 months and a standard deviation = 6 months.To test the alternative hypothesis that μ > 20 with α = .05, 36 laptop batteries are randomly selected.Assuming that μ = 21, the probability of type II error is approximately ________.

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Q115 Q115 Q115

A laptop battery lifespan follows a normal distribution with mean μ = 20 months and a standard deviation = 6 months.To test the alternative hypothesis that μ > 20 with α = .05, 36 laptop batteries are randomly selected.Assuming that μ = 21, the power of this is approximately ________.

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Q116 Q116 Q116

A recent survey suggests 30% of boat owners do not regularly use their boat after the second year of ownership.A local boat dealer wants to test the alternative hypothesis that p ≠ .30 with α = .05.He surveys 60 boat owners and finds 42% of the owners who have owned their boat for three years report they do not regularly use their boat.Assuming that p = .35, the probability of type II error is approximately ________.

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Q117 Q117 Q117

A recent survey suggests 30% of boat owners do not regularly use their boat after the second year of ownership.A local boat dealer wants to test the alternative hypothesis that p > .30 with α = .05.He surveys 60 boat owners and finds 42% of the owners who have owned their boat for three years report they do not regularly use their boat.Assuming that p = .35, the probability of type II error is approximately ________.

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Q118 Q118 Q118

A recent survey suggests 30% of boat owners do not regularly use their boat after the second year of ownership.A local boat dealer wants to test the alternative hypothesis that p > .30 with α = .05.He surveys 60 boat owners and finds 42% of the owners who have owned their boat for three years report they do not regularly use their boat.Assuming that p = .35, the power is approximately ________.

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Q119 Q119 Q119

A car manufacturer looks at past sales and realizes that the most common car color is silver with 24% of purchasers selecting that color.The dealerships in one state believe that car purchasers in their area believe that the proportion of purchasers selecting silver is greater than 24%.Based on a survey of 84 car purchasers in the state, the dealerships find that 26% of them would select silver.If the true proportion selecting silver is 27%, what is the probability of the dealerships making a Type II error, given an alpha of 0.05?

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Q120 Q120 Q120

A car manufacturer looks at past sales and realizes that the most common car color is silver with 24% of purchasers selecting that color.The dealerships in one state believe that car purchasers in their area believe that the proportion of purchasers selecting silver is greater than 24%.Based on a survey of 84 car purchasers in the state, the dealerships find that 26% of them would select silver.If the true proportion selecting silver is 27%, what is the power, given an alpha of 0.05?

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