MATH 302 Final Exam 1 - Question and Answers | COMPLETE GUIDE

MATH 302 Final Exam 1 - Question and Answers AMU Math 302 – Final Fall 2018 25/25 1. 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 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. 2. The data presented in the table below resulted from an experiment in which seeds of 5 different types were planted and the number of seeds that germinated within 5 weeks after planting was recorded for each seed type. At the .01 level of significance, is the proportion of seeds that germinate dependent on the seed type? Seed Type Observed Frequencies Germinated Failed to Germinate 1 31 7 2 57 33 3 87 60 4 52 44 5 10 19 A. Yes, because the test value 16.86 is greater than the critical value of 13.28 B. Yes, because the test value 16.86 is less than the critical value of 14.86 C. No, because the test value of 16.86 is greater than the critical value of 13.28 D. No, because the test value of 13.28 is less than the critical value of 16.86 3. An agent for a residential real estate company in a large city would like to be able to predict the monthly rental cost of 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. 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. 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 t-test value, 7.74, is greater than the critical value 1.96. D. 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. 4. 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, in feet, devoted to pet food and the weekly sales in hundreds of dollars. . Is the correlation between weekly sales and shelf space significant at the .01 level of significance? 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 20 Weekly Sales 2.3 2.7 2.8 2.6 2.9 3.1 Compute the value of the sample correlation coefficient between weekly sales and shelf space. A. 0.684 B. 0.827 C. 0.308 D. 0.652 5. The correlation value ranges from A. -1 to +1 B. 0 to +1 C. -2 to +2 D. -3 to +3 6. 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? Women Men Sample size 50 80 Mean effect 7 6.95 Sample variance 3 4 A. z = 0.455 B. t = 0.151 C. z = 0.081 D. t = 3.252 7. 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. Is there sufficient evidence to conclude, at the 10% significance level, that the two teams differ with respect to their proportions of unacceptable assemblies? A. No, since the p-value is less than 0.10 B. No, since the test value exceeds the critical value C. No, since the test value does not exceed the critical value D. Yes, since the p-value is greater than 0.10 8. The form of the alternative hypothesis can be: A. one-tailed B. one or two-tailed C. two-tailed D. neither one or two-tailed 9. Smaller p-values indicate more evidence in support of the: A. null hypothesis B. quality of the researcher C. the reduction of variance D. alternative hypothesis 10. The null and alternative hypotheses divide all possibilities into: A. two non-overlapping sets B. two sets that may or may not overlap C. two sets that overlap D. as many set as necessary to cover all possibilities 11. A sample of 25 different payroll departments found that the employees worked an average of 310.3 days a year with a 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