Math 302 Final Exam practice questions and answers 2021 questions and answers docs

Math 302 Final Exam practice questions and answers 2021 questions and answers docs Question 1 of 23 1.0/ 1.0 Points The chi-square goodness-of-fit test can be used to test for: A.significance of sample statistics B.difference between population means C.difference between population variances D.normality Question 2 of 23 1.0/ 1.0 Points A company operates four machines during three shifts each day. From production records, the data in the table below were collected. At the .05 level of significance test to determine if the number of breakdowns is independent of the shift.     Machine Shift A B C D 1 41 20 12 16 2 31 11 9 14 3 15 17 16 10 A.The number of breakdowns is dependent on the shift, because the test value 11.649 is less than the critical value of 12.592. B.The claim that the number of breakdowns is independent of the shift cannot be rejected, because the test value 11.649 is less than the critical value of 12.592. C.The number of breakdowns is dependent on the shift, because the p-value is .07. D.The number of breakdowns is independent of the shift, because the test value 12.592 is greater than the critical value of 11.649. Part 2 of 16 - 3.0/ 3.0 Points Question 3 of 23 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 number of outliers B.largest sum of squared residuals C.largest number of points on the line D.smallest sum of squared residuals Question 4 of 23 1.0/ 1.0 Points A linear regression analysis produces the equation y = 5.32 + (-0.846)x Which of the following statements must be true? A.As x increases, y increases, and the correlation coefficient must be positive. B.As x increases, y decreases, and the correlation coefficient must be positive. C.As x increases, y increases, and the correlation coefficient must be negative. D.As x increases, y decreases, and the correlation coefficient must be negative. Question 5 of 23 1.0/ 1.0 Points The standard error of the estimate, sest, is essentially the A.standard deviation of the explanatory variable B.mean of the explanatory variable C.mean of the residuals D.standard deviation of the residuals Part 3 of 16 - 1.0/ 2.0 Points Question 6 of 23 1.0/ 1.0 Points   A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at the .10 level of significance, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?     Pine trees Spruce trees Sample size 40 70 Mean trunk diameter (cm) 45 39 Sample variance 100 150 A. The data do not support the claim because the test value 1.29 is greater than 1.28. B.The data do not support the claim because the test value 1.29 is less than 1.64. C.The data support the claim because the test value 2.78 is greater than 1.28. D. The data support the claim because the test value 2.78 is greater than 1.64. Question 7 of 23 0.0/ 1.0 Points Multiple myeloma or blood plasma cancer is characterized by increased blood vessel formulation in the bone marrow that is a prognostic factor in survival. One treatment approach used for multiple myeloma is stem cell transplantation with the patient’s own stem cells. The following data represent the bone marrow microvessel density for a sample of 7 patients who had a complete response to a stem cell transplant as measured by blood and urine tests. Two measurements were taken: the first immediately prior to the stem cell transplant, and the second at the time of the complete response.   Patient 1 2 3 4 5 6 7 Before 158 189 202 353 416 426 441 After 284 214 101 227 290 176 290 Suppose you wanted to conduct a test of hypothesis to determine if there is sufficient evidence to conclude that the mean bone marrow microvessel density is higher before the stem cell transplant than after the stem cell transplant?  What is the p-value associated with the test of hypothesis you would conduct?  A.p = . B.p = . C.p = . D.p = . Part 4 of 16 - 2.0/ 3.0 Points Question 8 of 23 1.0/ 1.0 Points Which of the following values is not typically used for ? A.0.05 B.0.10 C.0.01 D.0.50 Question 9 of 23 0.0/ 1.0 Points  A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood 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? At the  = .01 level of significance, what is your conclusion? A.         Reject H0.  At the  = .01 level of significance, there is not enough evidence to support the claim that this technician’s true variance is larger than the target accuracy. B.Reject H0. At the   = .01 level of significance, there is enough evidence to support the claim that this technician’s variance is larger than the target accuracy. C.Cannot determine D.Do not reject H0. At the  = .01 level of significance there is not sufficient evidence to suggest that this technician’s true variance is greater than the target accuracy.  Question 10 of 23 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 popcorn is 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 serving to be 78 with a sample standard deviation of 7. At the  = .05 level of significance, does the nutritionist have enough evidence to reject the writer’s claim? A.Cannot Determine B.No C.Yes Part 5 of 16 - 2.0/ 2.0 Points Question 11 of 23 1.0/ 1.0 Points The t- distribution for developing a confidence interval for a mean has _____ degrees of freedom. A.n B.n + 1 C.n - 1 D.n - 2 Question 12 of 23 1.0/ 1.0 Points Compute     where t20 has a t-distribution with 20 degrees of freedom. A.0.5334 B.0.8233 C.0.1767 D.0.6466 Part 6 of 16 - 1.0/ 1.0 Points Question 13 of 23 1.0/ 1.0 Points The standard deviation of   is usually called the A.standard error of the mean B.standard error of the population C.randomized standard error D.standard error of the sample Part 7 of 16 - 1.0/ 1.0 Points Question 14 of 23 1.0/ 1.0 Points Suppose that 50 identical batteries are being tested. After 8 hours of continuous use, assume that a given battery is still operating with a probability of 0.70 and has failed with a probability of 0.30. What is the probability that greater than 40 batteries will last at least 8 hours? A.0.0402 B.0.0789 C.0.4538 D.0.9598 Part 8 of 16 - 1.0/ 1.0 Points Question 15 of 23 1.0/ 1.0 Points A jar contains four white marbles, five red marbles, and six black marbles. If a marble is selected at random, find the probability that it is white or black . A.2/15 B.2/3 C.1/5 D.2/5 Part 9 of 16 - 1.0/ 3.0 Points Question 16 of 23 1.0/ 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 MUST be 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. Staples, a chain of large office supply stores, sells a line of desktop and laptop computers. Company executives want to know whether the demands for these two types of computers are dependent on one another. Each day's demand for each type of computers is categorized as Low, Medium-Low, Medium-High, or High. The data shown in the table below is based on 200 days of operation. Based on these data, can Staples conclude that demands for these two types of computers are independent? Test at the 5% level of significance.       desktops           low med-low med-high high     low 3 14 14 4 35 laptops med-low 6 18 17 22 63   med-high 13 16 11 16 56   high 8 14 15 9 46     30 62 57 51 200 What is the test value for this hypothesis test? :   What is the critical value for this hypothesis test?  What is the conclusion for this hypothesis test?  Choose one. 1.  At the .05 level of significance, Staples can conclude that demands for these two types of computers are independent. 2. At the .05 level of significance, Staples can conclude that demands for these two types of computers are dependent. . Part 10 of 16 - 1.0/ 1.0 Points Question 17 of 23 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 MUST be 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, and direct 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 you derived? Place your answer, rounded to 1 decimal place, in the blank.  Do not use any stray punctuation marks or a percentage sign.  For example, 78.9 would be a legitimate entry.  95.6 Part 11 of 16 - 1.0/ 1.0 Points Question 18 of 23 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 MUST be 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. Two teams of workers assemble automobile engines at a manufacturing plant in Michigan. A random sample of 145 assemblies from team 1 shows 15 unacceptable assemblies. A similar random sample of 125 assemblies from team 2 shows 8 unacceptable assemblies. If you are interested in determining if there is sufficient evidence to conclude, at the 10% significance level, that the two teams differ with respect to their proportions of unacceptable assemblies, what is the test value you would use to conduct such a test of hypothesis? Place your answer, rounded to 2 decimal places, in the blank. For example, 2.34 would be a legitimate entry. Part 12 of 16 - 1.0/ 1.0 Points Question 19 of 23 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 MUST be 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 the average weekly earnings for employees in general automotive repair shops is $450, and that the standard deviation for the weekly earnings for such employees is $50. A sample of 100 such employees is selected at random. Find the probability that the mean of the sample is between $445 and $455. Place your answer, rounded to 4 decimal places, in the blank. For example, 0.2345 would be a legitimate entry. Part 13 of 16 - 1.0/ 1.0 Points Question 20 of 23 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 MUST be 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 sample has 25 observations and a 99% confidence estimate for    is needed, the appropriate value of the t-multiple required is .  Place your answer, rounded to 3 decimal places, in the blank. For example, 3.456 would be an appropriate entry. Part 14 of 16 - 0.0/ 1.0 Points Question 21 of 23 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 MUST be 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 complete set of results were reported. Use the following data to answer this question.       Number of Products Purchased   Brands Purchased Fewer Same More Total 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 fewer products than before and changed brands? Place your answer, rounded to 4 decimal places, in the blank Part 15 of 16 - 0.0/ 1.0 Points Question 22 of 23 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 MUST be 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 sea divers is greater than 450. To do so, she selected a random sample of 25 divers and found s = 468. Assuming that the systolic blood pressures of deep sea divers are normally distributed, if the doctor wanted to test her 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, 34.567 would be a legitimate e Part 16 of 16 - 0.0/ 1.0 Points Question 23 of 23 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 MUST be 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. An ice cream vendor sells three flavors: chocolate, strawberry, and vanilla. Forty five percent of the sales are chocolate, while 30% are strawberry, with the rest vanilla flavored. Sales are by the cone or the cup. The percentages of cones sales for chocolate, strawberry, and vanilla, are 75%, 60%, and 40%, respectively. For a randomly selected sale, define the following events: = chocolate chosen = strawberry chosen = vanilla chosen = ice cream on a cone ice cream in a cup Find the probability that the ice cream was strawberry flavor, given that it was sold on a cone. Place your answer, rounded to 4 decimal places, in the blank. For exampe, 0.3456 would be a legitimate entry.