MATH 302 Final Exam Questions & Answers 2022 - American University | RATED A

MATH 302 Final Exam Questions & Answers 2022 - American University | RATED AMATH 302 Final Exam 2022 - American University QUIZ 1 Question 1 of 20 1.0/ 1.0 Points Which of the following statements are false regarding a boxplot? A. The height of the box has no significance. B. Boxplots can be used to either describe a single variable in a data set or to compare two (or more)variables C. The length of the box equals the range of the data. D. The right and left of the box are the third and first quartiles Answer Key: C Question 2 of 20 1.0/ 1.0 Points A histogram that has a single peak and looks approximately the same to the left and right of the peak is called:A.balanced B.symmetri c C.proportio nal D.bimodal Answer Key: B Question 3 of 20 0.0/ 1.0 Points Suppose that a histogram of a data set is approximately symmetric and "bell shaped". Approximately what percentof the observations are within two standard deviations of the mean? A.95% B.50% C.68% D.99.7 % Answer Key: A Question 4 of 20 1.0/ 1.0 Points A population includes: A. only machines B. only households C. only people D. all objects of interest in a particular study Answer Key: D Question 5 of 20 1.0/ 1.0 Points The amount of time needed to run the Boston marathon is an example of which type of variable? A.discrete B.continuous C.none of the above D.qualitative Answer Key: B Question 6 of 20 1.0/ 1.0 Points Researchers may gain insight into the characteristics of a population by examining a A.sample of the populationB.replica C.mathematical model describing the populationD.description of the population Answer Key: A Question 7 of 20 1.0/ 1.0 Points If a variable has possible values –2, 6, and 17, then this variable is A. both a continuous and a discrete variable B. neither a continuous nor a discrete variable C.a continuous variable D.a discrete variable Answer Key: D Question 8 of 20 1.0/ 1.0 Points The total frequency of the data whose ogive is shown below is approximately A.1 2 B.9 0 C.1 8 D.3 4 Answer Key: D Question 9 of 20 1.0/ 1.0 Points Data that arise from counts are called:A.counted data B.discrete data C.nominal data D.continuous data Answer Key: B Question 10 of 20 1.0/ 1.0 Points The length of the box in the boxplot portrays the A.median B.interquartile rangeC.mean D.range Answer Key: B Question 11 of 20 1.0/ 1.0 Points Which measure of central location is meaningful when the data are categorical? A. The range B. The mean C. The mode D. The median Answer Key: C Question 12 of 20 1.0/ 1.0 Points A scatter plot would be useful for A. Showing the trend of sales, over time, of five different brands of blank DVDs B. Showing the top selling brands of blank DVDs C. Showing the relative number of sales of four different brands of blank DVDs D. Showing the relationship between the sales of blank CDs and blank DVDs Answer Key: D Part 2 of 3 - 6.0/ 6.0 Points Question 13 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A student scored 84 points on a test where the mean score was 79 and the standard deviation was 4. Find thestudent's z score, rounded to 2 decimal places, and place it in the blank. 1.25 Answer Key: 1.25 Question 14 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The following data represent the number of children in a sample of 10 families from Chicago: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2. Compute the variance of the data. Place your answer, rounded to two decimal places, in the blank. For example, 3.45 would be a legitimate entry. 2.77 Answer Key: 2.77 Question 15 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The following data represent the number of children in a sample of 10 families from Chicago: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2. Compute the median number of children. Place your answer, rounded to two decimal places, in the blank. Forexample, 3.45 would be a legitimate entry. 1.50 Answer Key: 1.50 Question 16 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result. Did Well in Exam Did Poorly in Exam Studying for Exam 60 15 Went Partying 22 53 Of those in the sample who went partying the weekend before the final exam, what percentage of themdid well in the exam? Place your answer in the blank, rounded to 2 decimal places. Do not use a percentage sign (%). For example, 44.44 would be a legitmate answer. 29.33 Answer Key: 29.33 Question 17 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The following data are the base salaries, in thousands of dollars, of 50 chief executive officers for a sample of companies doing business with the state of Connecticut. That is, the first entry in the table below corresponds to asalary of $125,000. A copy of this data set can be found in the Excel Workbook called CEOS. 125 157 113 127 201 165 145 119 148 158 14 8 168 117 105 136 136 125 148 10 8 178 179 191 225 20 104 4 20 5 197 119 20 9 157 20 9 205 221 178 247 23 5 217 222 22 4 187 26 5 148 165 22 8 239 24 5 152 148 115 150 Find the interquartile range of the CEO salaries, in thousands of dollars, rounded to 2 decimal places. Do not use adollar sign. Note: $177,760 should be recorded as 177.76. 69.75 CEOS Answer Key: 68.00|74.00 Question 18 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result. Did Well in Exam Did Poorly in Exam Studying for Exam 60 15 Went Partying 22 53 Of those in the sample who did well on the final exam, what percentage of them went partying the weekend before the exam? Place your answer in the blank, rounded to 2 decimal places. Do not use apercentage sign (%). For example, 44.44 would be a legitimate answer. 26.83 Answer Key: 26.83 Part 3 of 3 - 2.0/ 2.0 Points Question 19 of 20 1.0/ 1.0 Points Individual observations within each category may be found in a frequency table. True False Answer Key: False Question 20 of 20 1.0/ 1.0 Points The value of the standard deviation always exceeds that of the variance. Tru e Fals e Answer Key: False QUIZ 2 Question 1 of 20 1.0/ 1.0 Points The number of ways to choose two representatives from a committee of 13 people isA.156 B.78 C.13 ! D.55 Answer Key: B Question 2 of 20 0.0/ 1.0 Points If two events are independent, what is the probability that they both occur? A.0.0 B.0.5 C.1.00 D.Cannot be determined from the information given Answer Key: D Question 3 of 20 1.0/ 1.0 Points In a genetics experiment 5 flowers out of 8 were bicolor, and the rest were solid color. If 3 of the flowers areselected at random without replacement, what is the probability that all 3 are bicolor? A.0.625 B.0.24 41 C.0.375 D.0.178 6 Answer Key: D Question 4 of 20 1.0/ 1.0 Points Three cards are drawn from a deck without replacement. What is the probability that all three cards are clubs? A.0.015 6 B.0.012 9 C.0.012 D.0.25 Answer Key: B Question 5 of 20 1.0/ 1.0 Points If P(A) = P(A|B), then events A and B are said to beA.exhaustive B.independent C.complementar y D.mutually exclusive Answer Key: B Part 2 of 6 - 5.0/ 5.0 Points Question 6 of 20 1.0/ 1.0 Points The following data were obtained from a survey of college students. The variable X represents the number of non-assigned books read during the past six months. x 0 1 2 3 4 5 P (X=x) 0.2 0 0.2 5 0.20 0.15 0.1 0 0.1 0 What is the standard deviation of X? A.2.0 B.1.58 C.1.24 D.3.24 Answer Key: B Question 7 of 20 1.0/ 1.0 Points The following data were obtained from a survey of college students. The variable X represents the number of non-assigned books read during the past six months. x 0 1 2 3 4 5 P (X=x) 0.2 0 0.2 5 0.20 0.15 0.1 0 0.1 0 Find P(1 < X < 5) A.0.45 B.0.30 C.0.70 D.0.20 Answer Key: A Question 8 of 20 1.0/ 1.0 Points Find the variance of the following probability distribution. X P(X ) 1 0.10 2 0.35 3 0.10 4 0.15 5 0.3 0 A.1.44 B.2.06 C.1.76 D.1.2 Answer Key: B Question 9 of 20 1.0/ 1.0 Points Find the variance of the following probability distribution. X P(X ) 1 0.2 0 2 0.15 3 0.25 4 0.25 5 0.15 A.1.34 B.1.8 C.0.48 D.1.16 Answer Key: B Question 10 of 20 1.0/ 1.0 Points In one town 33% of the households have a vehicle with all-wheel drive. If 4 households are selected at random,what is the probability that all 4 have vehicles with all-wheel drive? A.0.46 62 B.0.08 25 C.0.011 9 D.0.33 Answer Key: C Part 3 of 6 - 3.0/ 4.0 Points Question 11 of 20 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. In February 2002 the Argentine peso lost 70% of its value compared to the United States dollar. This devaluation drastically raised the price of imported products. According to a survey conducted by AC Nielsen in April 2002, 68% of the consumers in Argentina were buying fewer products than before the devaluation, 24% were buying the same number of products, and 8% were buying more products. Furthermore, in a trend toward purchasing less- expensive brands, 88% indicated that they had changed the brands they purchased. Suppose the following completeset of results were reported. Use the following data to answer this question. Brands Purchased Number of Products Purchased Total Fewe r Sam e Mor e Same 10 14 24 48 Changed 262 82 8 352 Total 272 96 32 400 What is the probability that a consumer selected at random purchased the same number or more products thanbefore? Place your answer, rounded to 4 decimal places, in the blank. .6800 Answer Key: 0.3200 Question 12 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The following data were obtained from a survey of college students. The variable X represents the number of non-assigned books read during the past six months. x 0 1 2 3 4 5 6 P (X=x) 0.5 5 0.1 5 0.1 0 0.1 0 0.0 4 0.0 3 0.0 3 Find P(1 < X < 5). Place your answer, rounded to two decimal places in the blank. For example, 0.56 would be alegitimate entry. .24 Answer Key: 0.24 Question 13 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. If a gambler rolls two dice and gets a sum of four, he wins $10; and if he gets a sum of three, he wins $25. The cost toplay the game is $5. What is the expectation of this game? Place your answer, rounded to two decimal places, in the blank. -2.78 When entering your answer do not use a dollar sign. However, if the expected payoff is negative be sure to use a minus sign. For example, -1.23 would bea legitimate entry. Answer Key: -2.88|-2.68 Question 14 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Find the mean of the following probability distribution? 1 0.2 0 2 0.1 0 3 0.3 5 4 0.0 5 5 0.3 0 Place your answer, rounded to two decimal places, in the blank. 3.15 When entering your answer do not use any labels or symbols other than a decimal point. Simply provide the numerical value. For example, 1.23 would bea legitimate entry. Answer Key: 3.15 Part 4 of 6 - 2.0/ 4.0 Points Question 15 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. If you have six books, but there is room for only four books on the shelf, in how many ways can these books be arranged on the shelf? Place your answer in the blank. Do not use any decimal places or commas. For example, 45would be a legitimate entry. 360 Answer Key: 360 Question 16 of 20 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Mothers Against Drunk Driving (MADD) is a very visible group whose main focus is to educate the public about the harm caused by drunk drivers. A study was recently done that emphasized the problem we all face with drinking and driving. Five hundred accidents that occurred on a Saturday night were analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role in the accident. The numbers are shown below: Number of Vehicles Involved Did alcohol play a role? 1 2 3 Yes 60 110 30 200 No 40 215 45 300 100 325 75 Given alcohol was involved, what proportion of accidents involved a single vehicle? Place your answer, rounded to 2 decimal places, in the blank. For example, 0.23 is a legitimate entry. .12 Answer Key: 0.30 Question 17 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Suppose that a marketing firm sends questionnaires to two different companies. Based on historical evidence, the marketing research firm believes that each company, independently of the other, will return the questionnaire with aprobability of 0.30. What is the probability that both questionnaires will be returned? Place your answer, rounded to2 decimal places, in the blank. For example, 0.23 is a legitimate entry. .09 Answer Key: 0.09 Question 18 of 20 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A reading list for a course contains 20 articles. How many ways are there to choose three articles from this list? Place your answer in the blank. Do not use any decimal places or commas. For example, 45 would be a legitimateentry. 6840 Answer Key: 1140 Part 5 of 6 - 1.0/ 1.0 Points Question 19 of 20 1.0/ 1.0 Points If A and B are two independent events with P(A) = 0.20 and P(B) = 0.60, then P(A and B) = 0.80 Tru e Fals e Answer Key: False Part 6 of 6 - 1.0/ 1.0 Points Question 20 of 20 1.0/ 1.0 Points The variance of a binomial distribution for which n = 50 and p = 0.20 is 8.0. Tru e Fals e Answer Key: True QUIZ 3 Question 1 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Assume 50 random samples of the same sample size are taken from a population, and a 90% confidence interval isconstructed from each sample. How many of the intervals would you expect to contain the true population mean? Answer: 45 Round your answer to a whole number value as necessary. For example, 37 would be a legitimateentry. Answer Key: 45 Question 2 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Senior management of a consulting services firm is concerned about a growing decline in the firm’s weekly numberof billable hours. The firm expects each professional employee to spend at least 40 hours per week on work. In an effort to understand this problem better, management would like to estimate the standard deviation of the number ofhours their employees spend on work-related activities in a typical week. Rather than reviewing the records of all the firm’s full- time employees, the management randomly selected a sample of size 51 from the available frame. The sample mean and sample standard deviations were 48.5 and 7.5 hours, respectively. Construct a 95% confidence interval for the standard deviation of the number of hours this firm’s employees spendon work-related activities in a typical week. Place your LOWER limit, in hours, rounded to 1 decimal place, in the first blank. For example, 6.7 would be alegitimate entry. 6.3 Place your UPPER limit, in hours, rounded to 1 decimal place, in the second blank. For example, 12.3 would be alegitimate entry. 9.3 Answer Key: 6.2|6.4, 9.2|9.3 Question 3 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The percent defective for parts produced by a manufacturing process is targeted at 4%. The process is monitoreddaily by taking samples of sizes n = 160 units. Suppose that today’s sample contains 14 defectives. Determine a 95% confidence interval for the proportion defective for the process today. Place your LOWER limit, rounded to 3 decimal places, in the first blank. For example, 0.123 would be a legitimateanswer. .044 Place your UPPER limit, rounded to 3 decimal places, in the second blank. For example, 0.345 would be alegitimate entry. .131 Answer Key: 0.043|0.044, 0.130|0.133 Question 4 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A sample of 9 production managers with over 15 years of experience has an average salary of $71,000 and a samplestandard deviation of $18,000. Assuming that s = 18,000 is a reasonable estimate for what sample size would be needed to ensure that we couldestimate the true mean salary of all production managers with more than 15 years experience within $4200 if we wish to be 95% confident? Place your answer, as a whole number, in the blank. Do not use a dollar sign, a comma, or any other stray mark. For examples, 34 would be a legitimate entry. 71 Answer Key: 71 Question 5 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A survey of 85 families showed that 36 owned at least one DVD player. Find the 99% confidence interval estimateof the true proportion of families who own at least one DVD player. Place your limits, rounded to 3 decimal places, in the blanks. Place the lower limit in the first blank .285 and the upper limit in the second blank .562 When entering your answer do not use any labels or symbols other than the decimal point. Simply provide thenumerical values. For example, 0.123 would be a legitimate entry. Answer Key: 0.275|0.295, 0.552|0.572 Question 6 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. After calculating the sample size needed to estimate a population proportion to within 0.05, you have been told thatthe maximum allowable error (E) must be reduced to just 0.025. If the original calculation led to a sample size of 1000, the sample size will now have to be 4000 . Place your answer, as a whole number in the blank. For example, 2345 would be a legitimate entry. Answer Key: 4000 Question 7 of 20 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The personnel department of a large corporation wants to estimate the family dental expenses of its employees todetermine the feasibility of providing a dental insurance plan. A random sample of 12 employees reveals the following family dental expenses (in dollars): 115, 370, 250, 593, 540, 225, 177, 425, 318, 182, 275, and 228. Construct a 95% confidence interval estimate for the standard deviation of family dental expenses for all employeesof this corporation. Place your LOWER limit, in dollars rounded to 1 decimal place, in the first blank. Do not use a dollar sign, acomma, or any other stray mark. For example, 123.4 would be a legitimate entry. 214.2 Place your UPPER limit, in dollars rounded to 1 decimal place, in the second blank. Do not use a dollar sign, acomma, or any other stray mark. For example, 567.8 would be a legitimate entry. 402.6 Answer Key: 104.7|104.9, 251.1|251.3 Part 2 of 3 - 10.0/ 11.0 Points Question 8 of 20 1.0/ 1.0 Points The t- distribution for developing a confidence interval for a mean has degrees of freedom. A.n - 1 B.n + 1 C.n - 2D.n Answer Key: A Question 9 of 20 1.0/ 1.0 Points In a study of elephants a researcher wishes to determine the average weight of a certain subspecies of elephants. From previous studies, the standard deviation of the weights of elephants in this subspecies is known to be 1500 pounds. How many elephants does the researcher need to weigh so that he can be 80% confident that the averageweight of elephants in his sample is within 350 pounds of the true average weight for this subspecies? A.31 B.50 C.16 6 D.39 Answer Key: A Question 10 of 20 1.0/ 1.0 Points Which of the following will make a confidence interval narrower and more precise? A. Larger sample size and lower confidence level B. Smaller sample size and lower confidence level C. Smaller sample size and higher confidence level D. Larger sample size and higher confidence level Answer Key: A Question 11 of 20 1.0/ 1.0 Points If you are constructing a confidence interval for a single mean, the confidence interval will with anincrease in the sample size. A. increase B. increase or decrease, depending on the sample dataC.decrease D.stay the same Answer Key: C Question 12 of 20 1.0/ 1.0 Points Confidence intervals are a function of which of the following three things? A.The data in the sample, the confidence level, and the sample size B. The sampling distribution, the confidence level, and the degrees of freedom C. The population, the sample, and the standard deviation D. The sample, the variable of interest, and the degrees of freedom Answer Key: A Question 13 of 20 1.0/ 1.0 Points A researcher wishes to know, with 98% confidence, the percentage of women who wear shoes that are too small fortheir feet. A previous study conducted by the Academy of Orthopedic Surgeons found that 80% of women wear shoes that are too small for their feet. If the researcher wants her estimate to be within 3% of the true proportion, how large a sample is necessary? A.96 6 B.68 3 C.18 3 D.48 4 Answer Key: A Question 14 of 20 1.0/ 1.0 Points From a sample of 500 items, 30 were found to be defective. The point estimate of the population proportiondefective will be: A.16.66 7 B.30 C.0.60 D..06 Answer Key: D Question 15 of 20 1.0/ 1.0 Points The average gas mileage of a certain model car is 26 miles per gallon. If the gas mileages are normally distributedwith a standard deviation of 1.3, find the probability that a randomly selected car of this model has a gas mileage between 25.8 and 26.3 miles per gallon. A.0.15 B.0.85 C.0.70 D.0.30 Answer Key: A Question 16 of 20 0.0/ 1.0 Points Compute where t15 has a t-distribution with 15 degrees of freedom. A.0.936 06 B.0.968 03 C.0.763 9 D.0.031 97 Answer Key: D Question 17 of 20 1.0/ 1.0 Points A sample of 25 different payroll departments found that the employees worked an average of 310.3 days a year witha standard deviation of 23.8 days. What is the 90% confidence interval for the average days worked by employees in all payroll departments? A.301.0 < < 319.6 B.298.0 < < 322.6 C.302.2 < < 318.4 D.314.1 < < 316.8 Answer Key: C Question 18 of 20 1.0/ 1.0 Points A food snack manufacturer samples 15 bags of pretzels off the assembly line and weighed their contents. If the sample mean is 10.0 and the sample standard deviation is 0.15, find the 95% confidence interval estimate for thetrue mean. A.(9.96, 10.04) B.(9.68, 10.32) C.(9.97, 10.80) D.(9.92, 10.08) Answer Key: D Part 3 of 3 - 2.0/ 2.0 Points Question 19 of 20 1.0/ 1.0 Points The upper limit of the 95% confidence interval for the population proportion p, given that n = 300; and = 0.10is approximately 0.1339. Tru e Fals e Answer Key: True Question 20 of 20 1.0/ 1.0 Points In developing a confidence interval for the population standard deviation, , we make use of the fact that the sampling distribution of the sample standard deviation s is not the normal distribution or the t-distribution, but rather a right-skewed distribution called the chi-square distribution, which (for this procedure) has n – 1 degrees offreedom. Tru e Fals e QUIZ 4 Question 1 of 20 1.0/ 1.0 Points A two-tailed test is one where: A. negative sample means lead to rejection of the null hypothesis B. no results lead to the rejection of the null hypothesis C. results in either of two directions can lead to rejection of the null hypothesis D. results in only one direction can lead to rejection of the null hypothesis Answer Key: C Question 2 of 20 1.0/ 1.0 Points The hypothesis that an analyst is trying to prove is called the:A.level of significance B.quality of the researcher C.elective hypothesis D.alternative hypothesis Answer Key: D Question 3 of 20 1.0/ 1.0 Points You conduct a hypothesis test and you observe values for the sample mean and sample standard deviation when n =25 that do not lead to the rejection of H0. You calculate a p-value of 0.0667. What will happen to the p-value if youobserve the same sample mean and standard deviation for a sample size larger than 25? A. The p – value may increase or decrease B. The p – value decreases C. The p – value stays the same D. The p – value increases Answer Key: B Question 4 of 20 1.0/ 1.0 Points Which of the following statements are true of the null and alternative hypotheses? A. It is possible for neither hypothesis to be true B. Both hypotheses must be true C.Exactly one hypothesis must be true D.It is possible for both hypotheses to be true Answer Key: C Question 5 of 20 1.0/ 1.0 Points Which of the following values is not typically used for ? A.0.05 B.0.50 C.0.01 D.0.10 Answer Key: B Question 6 of 20 1.0/ 1.0 Points In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcornis 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per servingto be 78 with a sample standard deviation of 7. At the claim? .05 level of significance, does the nutritionist have enough evidence to reject the writer’s A.Cannot DetermineB.No C.Yes Answer Key: B Question 7 of 20 1.0/ 1.0 Points In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcornis 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per servingto be 78 with a sample standard deviation of 7. State the null and alternative hypotheses. A.H0: = 75, H1: > 75 B.H0: 75, H1: > 75 C.H0: = 75, H1: ≠ 75 D.H0: 75, H1: < 75 Answer Key: C Question 8 of 20 1.0/ 1.0 Points A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the sameblood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy? Compute the value of the appropriate test statistic. A.z = 1.65 B.t = 27.50 C. = 30.58 D. = 27.50 Answer Key: D Question 9 of 20 1.0/ 1.0 Points Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance. What is your conclusion? A. Do not reject H0. There is not enough evidence to support the claim that the proportion of students planning to go to college is greater than .79. B. Reject H0. There is enough evidence to support the claim that the proportion of students planning to go to college is now greater than .79. C. Cannot determine D. More seniors are going to college Answer Key: A Question 10 of 20 1.0/ 1.0 Points A null hypothesis can only be rejected at the 5% significance level if and only if:A.the null hypothesis is biased B.a 95% confidence interval includes the hypothesized value of the parameterC.the null hypotheses includes sampling error D.a 95% confidence interval does not include the hypothesized value of the parameter Answer Key: D Question 11 of 20 0.0/ 1.0 Points A manufacturer of flashlight batteries took a sample of 13 batteries from a day’s production and used them continuouslyuntil they failed to work. The life lengths of the batteries, in hours, until they failed were: 342, 426, 317, 545, 264, 451, 1049, 631, 512, 266, 492, 562, and 298. At the .05 level of significance, is there evidence to suggest that the mean life length of the batteries produced bythis manufacturer is more than 400 hours? A. Yes, because the test value 1.257 is less than the critical value 2.179 B. Yes, because the test value 1.257 is less than the critical value 1.782 C. No, because the test value 1.257 is greater than the critical value 1.115 D. No, because the p-value for this test is equal to .1164 Answer Key: D Part 2 of 3 - 4.0/ 6.0 Points Question 12 of 20 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Suppose a firm that produces light bulbs wants to know whether it can say that its light bulbs typically last more than 1500 hours. Hoping to find support for their claim, the firm collects a random sample of n = 25 light bulbs andrecords the lifetime (in hours) of each bulb. The information related to the hypothesis test is presented below. Test of H0: 1500 versus H1: > 1500Sample mean 1509.5 Std error of mean 4.854 Assuming the life length of this type of lightbulb is normally distributed, what is the p-value associated with thistest? Place your answer, rounded to 3 decimal places in the blank. For example, .123 would be a legitimate entry. .000 Answer Key: .031 Question 13 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Let x be a random variable representing dividend yield of Australian bank stocks. We may assume that x has a normal distribution with = 2.8%. A random sample of 16 Australian bank stocks has a sample mean dividend yield of 8.91%. For the entire Australian stock market, the mean dividend yield is = 6.4%. If you wanted to testto determine if these data indicate that the dividend yield of all Australian bank stocks is higher than 6.4%, what is the value of the test statistic? Place your answer, rounded to 3 decimal places, in the blank. For example, 2.345 would be a legitimate entry. 3.586 Answer Key: 3.586 Question 14 of 20 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Let x be a random variable representing dividend yield of Australian bank stocks. We may assume that x has a normal distribution with = 2.8%. A random sample of 16 Australian bank stocks has a sample mean dividend yield of 8.91%. For the entire Australian stock market, the mean dividend yield is = 6.4%. If you wanted to test,at a .05 level of significance, to determine if these data indicate that the dividend yield of all Australian bank stocksis higher than 6.4% what is the critical value that you would use? Place your answer, rounded to 2 decimal places, in the blank. For example, 2.34 would be a legitimate entry. 1.64 Answer Key: 1.65 Question 15 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The CEO of a software company is committed to expanding the proportion of highly qualified women in the organization’s staff of salespersons. He believes that the proportion of women in similar sales positions across thecountry is less than 45%. Hoping to find support for his belief, he directs you to test H0: p .45 vs H1: p < .45. In doing so, you collect a random sample of 50 salespersons employed by his company, which is thought to be representative of sales staffs of competing organizations in the industry. The collected random sample of size 50showed that only 18 were women. What is the smallest level of significance at which you could reject the null in favor of the alternative hypothesis?Place your answer, rounded to 4 decimal places, in the blank. For example, 0.1234 would be a legitimate entry. .1004 Answer Key: .1003|.1020 Question 16 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The ABC battery company claims that their batteries last 100 hours, on average. You decide to conduct a test to seeif the company's claim is true. You believe that the mean life may be different from the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below. Test of H0: = 100 versus H1: 100Sample mean 98.5 Std error of mean 0.777 Assuming the life length of batteries is normally distributed, if you wish to conduct this test at the 0.05 level of significance, what are the critical values that you should use? Place the smaller critical value, rounded to 3 decimal places, in the first blank. For example, -1.234 would be a legitimate entry. -2.093 . Place the larger critical value,rounded to 3 decimal places, in the second blank. For example, 1.234 would be a legitimate entry. 2.093 Answer Key: -2.093, 2.093 Question 17 of 20 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A medical doctor wishes to test the claim that the standard deviation of the systolic blood pressure of deep seadivers is less than 450. To do so, she selected a random sample of 20 divers and found s = 432. Assuming that the systolic blood pressures of deep sea divers are normally distributed, if the doctor wanted to testher research hypothesis at the .01 level of significance, what is the critical value? Place your answer, rounded to 3 decimal places, in the blank. For example, 4.567 would be a legitimate entry.7.633 Answer Key: 7.633 Part 3 of 3 - 3.0/ 3.0 Points Question 18 of 20 1.0/ 1.0 Points The probability of making a Type I error and the level of significance are the same. Tru e Fals e Answer Key: True Question 19 of 20 1.0/ 1.0 Points The p-value of a test is the smallest level of significance at which the null hypothesis can be rejected. Tru e Fals e Answer Key: True Question 20 of 20 1.0/ 1.0 Points An alternative or research hypothesis is usually the hypothesis a researcher wants to prove. Tru e Fals e Answer Key: True Quiz 5 Question 1 of 17 0.0/ 1.0 Points Two teams of workers assemble automobile engines at a manufacturing plant in Michigan. A random sample of 145assemblies from team 1 shows 15 unacceptable assemblies. A similar random sample of 125 assemblies from team 2 shows 8 unacceptable assemblies. Is there sufficient evidence to conclude, at the 10% significance level, that the two teams differ with respect to theirproportions of unacceptable assemblies? A. No, since the p-value is less than 0.10 B. Yes, since the p-value is greater than 0.10 C. No, since the test value does not exceed the critical value D. No, since the test value exceeds the critical value Answer Key: C Question 2 of 17 1.0/ 1.0 Points A pharmaceutical company is testing the effectiveness of a new drug for lowering cholesterol. As part of this trial,they wish to determine whether there is a difference between the effectiveness for women and for men. Assume α = 0.05. What is the test value? 5 Sample varianceA.t = 3.252 3 4 B.z = 0.081 C.z = 0.455 D.t = 0.151 Answer Key: D Question 3 of 17 1.0/ 1.0 Points A researcher hypothesizes that the variation in the amount of money spent on business dinners is greater than thevariation of the amount of money spent on lunches. The variance of nine business dinners was $6.12 and the variance of 12 business lunches was $0.87. What is the test value? A.9.61 B.7.03 C.3.10 D.49.5 0 Answer Key: B Part 2 of 8 - 5.0/ 5.0 Points Question 4 of 17 1.0/ 1.0 Points A correlation value of zero indicates. A.a strong linear relationship B.a weak linear relationship C.a perfect linear relationshipD.no linear relationship Answer Key: D Question 5 of 17 1.0/ 1.0 Points In choosing the “best-fitting” line through a set of points in linear regression, we choose the one with the:A.smallest sum of squared residuals B. smallest number of outliers C. largest sum of squared residuals D. largest number of points on the line Answer Key: A Question 6 of 17 1.0/ 1.0 Points In a simple linear regression analysis, the following sum of squares are produced: = 500 = 100 = 400 The proportion of the variation in Y that is explained by the variation in X is:A.25% B.50 % C.20 % D.80 % Answer Key: D Question 7 of 17 1.0/ 1.0 Points The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of pet food. For a random sample of 12 similar stores, she gathered the following information regarding the shelf space, infeet, devoted to pet food and the weekly sales in hundreds of dollars. Store 1 2 3 4 5 6 Shelf Space 5 5 5 10 10 10 Weekly Sales 1.6 2.2 1.4 1.9 2.4 2. 6 Store 7 8 9 10 11 12 Shelf Space 15 15 15 20 20 20 Weekly Sales 2.3 2.7 2.8 2. 6 2. 9 3.1 What is the estimated regression equation? A. = 1.45 + 0.724x B. = 2.63 + 0.724x C. = 1.45 + 0.074x D. = 2.63 - 0.174x Answer Key: C Question 8 of 17 1.0/ 1.0 Points An agent for a residential real estate company in a large city would like to be able to predict the monthly rental costof apartments based on the size of the apartment. Data for a sample of 25 apartments in a particular neighborhood are provided in the worksheet Apartments in the Excel workbook A. A At the .05 level of significance determine if the correlation between rental cost and apartment size is significant. A. No, there is not a statistically significant linear relationship between monthly rental cost and apartment size, because the sample correlation coefficient is less than .95. B. Yes, there is a statistically significant linear relationship between monthly rental cost and apartment size, because the p-value for this test is less than .0001. C. Yes, there is a statistically significant linear relationship between monthly rental cost and apartment size, because the sample correlation coefficient 0.85 exceeds 0.50. D. Yes, there is a statistically significant linear relationship between monthly rental cost and apartmentsize, because the t-test value, 7.74, is greater than the critical value 1.96. Answer Key: B Part 3 of 8 - 1.0/ 2.0 Points Question 9 of 17 1.0/ 2.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A business major wants to determine whether the variation in advertising costs of hair salons is different from thevariation in advertising costs of nail salons. He surveys several businesses and finds the standard deviation in monthly advertising costs is $23 for 12 hair salons, and $43 for 8 nail salons. What is the test value for this hypothesis test? Test value: 3.50 Round your answer to two decimal places.At the 0.05 level of significance, what is the critical value? Critical value:3.01 Round your answer to two decimal places. Answer Key: 3.50, 3.76 Feedback: This is a test of the difference between two variances. The test value F is found using the formula onpage 509: This is a two-tail test with alpha = 0.05. From Table H for alpha = 0.05/2 = 0.025 with dfN = 7 and dfD = 11, the critical value is 3.76. Since the F test value is less than the critical value, there is not sufficient evidence to showthat the variation in ad costs for hair salons is different from the ad costs for nail salons. Part 4 of 8 - 2.0/ 2.0 Points Question 10 of 17 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A company has observed that there is a linear relationship between indirect labor expense (ILE) , in dollars, anddirect labor hours (DLH). Data for direct labor hours and indirect labor expense for 18 months are given in the file ILE_and_DLH.xlsx Treating ILE as the response variable, use regression to fit a straight line to all 18 data points. Approximately what percentage of the variation in indirect labor expenses is explained by the regression model youderived? Place your answer, rounded to 1 decimal place, in the blank. Do not use any stray punctuation marks ora percentage sign. For example, 78.9 would be a legitimate entry. 95.6 Answer Key: 95.6 Question 11 of 17 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The marketing manager of a large supermarket chain would like to determine the effect of shelf space (in feet) on the weekly sales of international food (in hundreds of dollars). A random sample of 12 equal –sized stores is selected, with the following results: Store Shelf Space(X) Weekly Sales(Y) 1 10 2.0 2 10 2.6 3 10 1.8 4 15 2.3 5 15 2.8 6 15 3.0 7 20 2.7 8 20 3.1 9 20 3.2 10 25 3.0 11 25 3.3 12 25 3.5 Find the equation of the regression line for these data. What is the value of the coefficient of determination? Placeyour answer, rounded to 3 decimal places, in the blank. Do not use a dollar sign. For example, 0.345 would be a legitimate entry. .684 Answer Key: 0.684 Part 5 of 8 - 1.0/ 2.0 Points Question 12 of 17 1.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Q-Mart is interested in comparing its male and female customers. Q-Mart would like to know if the amount ofmoney spent by its female charge customers differs, on average, from the amount spent by its male charge customers. To answer this question, an analyst collected random samples of 25 female customers and 22 male customers. Based on these samples, on average, the 25 women charge customers spent $102.23 and the 22 men charge customers spent $86.46. Moreover, the sample standard deviation of the amount charged by the 25 women was $93.393, and the sample standard deviation of the amount charged by the 22 men was $59.695. Suppose, using a 10% level of significance, you wish to know if there is sufficient evidence for Q-Mart to concludethat, on average, the amount spent by women charge customers differs from the amount spent by men charge customers. That is suppose you wish to test H0: versus H1: Assuming that the amounts spent by female and male charge customers at Q-Mart are normally distributed, based on the procedure advocated by Bluman, what is/are the critical values that you would use to conduct this test of hypothesis? Place your answer, rounded to 3 decimal places, in the blank. If there are two critical values, place only the positive value in the blank. For example, 2.035 would be a legitimate entry. 1.721 Answer Key: 1.721 Question 13 of 17 0.0/ 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Are America's top chief executive officers (CEOs) really worth all that money? One way to answer this question is to look at the annual company percentage increase in revenue versus the CEO's annual percentage salary increase inthat same company. Suppose that a random sample of companies yielded the following data: percent change for corporation 15 6 12 3 12 28 6 8 2 percent change for CEO 17 -4 12 32 -1 7 2 Do these data indicate that the population mean percentage increase in corporate revenue is greater than the population mean percentage increase in CEO salary? Use a 5% level of significance. What is the test value that youwould use to conduct this test of hypothesis? Place your answer, rounded to 3 decimal places, in the blank. For example, 2.345 would be a legitimate entry. -1.761 Answer Key: 1.010 Part 6 of 8 - 2.0/ 3.0 Points Question 14 of 17 2.0/ 3.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (- ), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUSTbe used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Researchers conducted an experiment to measure the effect of a drug on improving the quality of sleep as determined by how many more minutes of REM sleep were measured for each participant. One group of participants were given the experimental drug; the other (control) group was given a placebo. Does the evidenceindicate that the drug improved the amount of REM sleep at a 0.01 level of significance? Answer each of the following parts. Experimental group Control group sample size 35 50 mean sleep improvement 12.8 9.1 sample variance 56.3 61.2 What is the test value for this hypothesis test? Answer: 2.20 Round your answer to two decimal places.What is the P-value for this hypothesis test? Answer: 0.015 Round your answer to three decimal places. What is the conclusion of this hypothesis test? Choose one. 1. There is sufficient evidence to show that the experimental drug improved the quality of sleep. 2. There is not sufficient evidence to show that the experimental drug improved the quality of sleep. 3. There is sufficient evidence to show that the quality of sleep is different for the experimental drug than for thecontrol drug. 4. There is not sufficient evidence to show that the control drug decreased the quality of sleep. Answer: 2 Enter only a 1, 2, 3 or 4 for your answer. Answer Key: 2.20, 0.017, 2 Feedback: This is a t-test of independent samples. Use the formula on page 480 to compute the t test value: This is a right-tail test with test value t = 2. and df = 34 (using the smaller sample size). The P-value is0.0174 using TDIST(2.,34,1) or the Critical Values workbook. Because the P-value is greater than alpha (0.01), there is not sufficient evidence to show that the experimental drugimproved the quality of sleep. Part 7 of 8 - 0.0/ 1.0 Points Question 15 of 17 0.0/ 1.0 Points When testing the equality of two population variances, the test statistic is the ratio of the population variances;namely . Tru e Fals e Answer Key: False Part 8 of 8 - 1.0/ 2.0 Points Question 16 of 17 1.0/ 1.0 Points In a simple linear regression problem, if the coefficient of determination is 0.95, this means that 95% of thevariation in the explanatory variable X can be explained by regression. True False Answer Key: False Question 17 of 17 0.0/ 1.0 Points In simple linear regression analysis, the relationship between the response variable Y and the explanatory variableX is a straight line. This means that all data points lie on the line. Tru e Fals e Answer Key: False Midterm Question 1 of 25 1.0/ 1.0 Points Which of the following statements is true for the following data values: 7, 5, 6, 4, 7, 8, and 12? A. Only the median and mode are equal B. The mean, median and mode are all equal C. Only the mean and mode are equal D. Only the mean and median are equal Answer Key: B Part 2 of 9 - 2.0/ 2.0 Points Question 2 of 25 1.0/ 1.0 Points If a menu has a choice of 4 appetizers, 4 main courses, and 3 desserts, then the sample space for all possible dinnershas how many outcomes? A.4 8 B.1 6 C.2 8 D.3 Answer Key: A Question 3 of 25 1.0/ 1.0 Points If a die is rolled one time, find the probability of getting a number greater than 2. A.2 B.-1 C.5/ 6 D.4/ 6 Answer Key: D Part 3 of 9 - 3.0/ 3.0 Points Question 4 of 25 1.0/ 1.0 Points Find the variance of the following probability distribution. X P(X ) 1 0.10 2 0.35 3 0.10 4 0.15 5 0.3 0 A.1.44 B.2.06 C.1.76 D.1.2 Answer Key: B Question 5 of 25 1.0/ 1.0 Points The following data were obtained from a survey of college students. The variable X represents the number of non-assigned books read during the past six months. P (X=x) 0.20 0.25 0.20 0.15 0.10 0.10 Find P( X 3) A.0.1 5 B.0.85 C.0.80 D.0.20 Answer Key: C Question 6 of 25 1.0/ 1.0 Points A discrete probability distribution: A. lists all of the possible values of the random variable and their corresponding probabilities B. is a tool that can be used to incorporate uncertainty into models C. can be estimated from long-run proportions D. is the distribution of multiple random variables Answer Key: A Part 4 of 9 - 5.0/ 6.0 Points Question 7 of 25 1.0/ 1.0 Points In a normal distribution, changing the standard deviation:A.makes the curve more robust B. shifts the curve left or right C. splits the distribution to two curves D. makes the curve more or less spread out Answer Key: D Question 8 of 25 1.0/ 1.0 Points Given that Z is a standard normal variable, the value z for which P(Z < z) = 0.2580 isA.0.242 B.0.75 8C.- 0.65 D.-0.70 Answer Key: C Question 9 of 25 1.0/ 1.0 Points One reason for standardizing random variables is to measure variables with:A.different means and standard deviations on a single scale B.different means and standard deviations on a non- standard scaleC.dissimilar means and similar standard deviations in like terms D.similar means and standard deviations on two scales Answer Key: A Question 10 of 25 1.0/ 1.0 Points The standard deviation of a probability distribution must be: A.a nonnegative number B.less than the value of the mean C.a negative number D.a number between 0 and 1 Answer Key: A Question 11 of 25 1.0/ 1.0 Points The continuous distribution characterized by a symmetric, bell-shaped curve is the: