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Chapter 9 : Transportation and Assignment Models 1. If the total demand equals the total supply in a transportation problem, the problem is a. degenerate. b. balanced. c. unbalanced. d. infeasible. 2. If a transportation problem has 4 sources and 5 destinations, the linear program for this will have a. 4 variables and 5 constraints. b. 5 variable and 4 constraints. c. 9 variables and 20 constraints. d. 20 variables and 9 constraints. 3. In a transportation problem, what indicates that the minimum cost solution has been found? a. all improvement indices are negative or zero b. all improvement indices are positive or zero c. all improvement indices are equal to zero d. all cells in the dummy row are empty 4. An assignment problem may be viewed as a transportation problem with a. a cost of $1 for all shipping routes. b. all supplies and demands equal to 1. c. only demand constraints. d. only supply constraints. 5. If the number of filled cells in a transportation table does not equal the number of rows plus the number of columns minus 1, then the problem is said to be a. unbalanced. b. degenerate. c. optimal. d. maximization problem. 6. If a solution to a transportation problem is degenerate, then a. it will be impossible to evaluate all empty cells without removing the degeneracy. b. a dummy row or column must be added. c. there will be more than one optimal solution. d. the problem has no feasible solution. 7. If the total demand is greater than the total capacity in a transportation problem, then a. the optimal solution will be degenerate. b. a dummy source must be added. c. a dummy destination must be added. d. both a dummy source and a dummy destination must be added.

8. In solving a facility location problem in which there are two possible locations being considered, the transportation algorithm may be used. In doing this, a. two rows (sources) would be added to the existing rows and the enlarged problem would be solved. b. two separate transportation problems would be solved. c. costs of zero would be used for each of the new facilities. d. the problem would be a transshipment problem. 9. The Hungarian method is a. a way to develop an initial solution to a transportation problem. b. used to solve assignment problems. c. also called Vogel’s approximation method. d. only used for problems in which the objective is to maximize profit. 10. In an assignment problem, it may be necessary to add more than one row to the table. a. True b. False 11. When using the Hungarian method, an optimal assignment can always be made when every row and every column has at least one zero. a. True b. False 12. An assignment problem can be viewed as a special type of transportation problem with which of the following features? a. the capacity for each source and the demand for each destination is equal to one b. the number of rows is equal to the number of columns c. the cost for each shipping route is equal to one d. all of the above solution : 1. b 2. d 3. b 4. b 5. b 6. a 7. b 8. b 9. b 10. a 11. b 12. a

Chapter 10 : Integer Programming, Goal Programming, and Nonlinear Programming 1. If all of the decision variables require integer solutions, the problem is a. a pure integer programming type of problem. b. a simplex method type of problem. c. a mixed-integer programming type of problem. d. a Gorsky type of problem. 2. In a mixed-integer programming problem a. some integers must be even and others must be odd. b. some decision variables must require integer results only and some variables must allow for continuous results. c. different objectives are mixed together even though they sometimes have relative priorities established. 3. A model containing a linear objective function and linear constraints but requiring that one or more of the decision variables take on an integer value in the final solution is called a. an integer programming problem. b. a goal programming problem. c. a nonlinear programming problem. d. a multiple objective LP problem. 4. An integer programming solution can never produce a greater profit than the LP solution to the same problem. a. True b. False 5. In goal programming, if all the goals are achieved, the value of the objective function will always be zero. a. True b. False 6. The objective in a goal programming problem with one priority level is to maximize the sum of the deviational variables. a. True b. False 7. Nobel Laureate Herbert A. Simon of Carnegie-Mellon University says that modern managers should always optimize, not satisfice. a. True b. False 8. The fixed charge problem is typically classified as a. a goal programming problem. b. a 0–1 integer problem. c. a quadratic programming problem. d. an assignment problem.

9. The 0–1 integer programming problem a. requires the decision variables to have values between 0 and 1. b. requires that the constraints all have coefficients between 0 and 1. c. requires that the decision variables have coefficients between 0 and 1. d. requires the decision variables to be equal to 0 or 1. 10. Goal programming a. requires only that you know whether the goal is direct profit maximization or cost minimization. b. allows you to have multiple goals. c. is an algorithm with the goal of a quicker solution to the pure integer programming problem. d. is an algorithm with the goal of a quicker solution to the mixedinteger programming problem. 11. Nonlinear programming includes problems a. in which the objective function is linear but some constraints are not linear. b. in which the constraints are linear but the objective function is not linear. c. in which both the objective function and all of the constraints are not linear. d. solvable by quadratic programming. e. all of the above. solution : 1. a 2. B 3. a 4. a 5. a 6. b 7. b 8. b 9. d 10. b 11. e

Chapter 12 : Project Management 1. Network models such as PERT and CPM are used a. to plan large and complex projects. b. to schedule large and complex projects. c. to monitor large and complex projects. d. to control large and complex projects. . 2. The primary difference between PERT and CPM is that a. PERT uses one time estimate. b. CPM has three time estimates. d. with CPM, it is assumed that all activities can be performed at the same time. 3. The earliest start time for an activity is equal to b. the smallest EF of the immediate predecessors. c. the largest ES of the immediate predecessors. d. the smallest ES of the immediate predecessors 4. The latest finish time for an activity is found during the backward pass through the network. The latest finish time is equal to a. the largest LF of the activities for which it is an immediate predecessor. b. the smallest LF of the activities for which it is an immediate predecessor. c. the largest LS of the activities for which it is an immediate predecessor. . 5. When PERT is used and probabilities are found, one of the assumptions that is made is that a. all activities are on the critical path. c. all activities have the same variance. d. the project variance is equal to the sum of the variances of all activities in the project. e. all of the above.

6. In PERT, the time estimate b represents a. the most optimistic time. b. the most likely time. . d. the expected time. e. none of the above. 7. In PERT, slack time equals a. ES + t – c. 0. d. EF - ES e. none of the above. 8. The standard deviation for the PERT project is approximately b. the sum of the critical path activity standard deviations. c. the square root of the sum of the variances of the project activities. d. all of the above. e. none of the above. 9. The critical path is the a. shortest path in a network. . c. path with the smallest variance. d. path with the largest variance. e. none of the above. 10. If the project completion time is normally distributed and the due date for the project is greater than the expected EF - ES. LS - ES. ES + t. completion time, then the probability that the project will be finished by the due date is a. less than 0.50. c. equal to 0.50. d. undeterminable without more information. 11. If activity A is not on the critical path, then the slack for A will equal – b. EF- ES c. 0. d. all of the above.

12. If a project is to be crashed at the minimum possible additional cost, then the first activity to be crashed must be . b. the one with the shortest activity time. c. the one with the longest activity time. d. the one with the lowest cost. 13. ______________ activities are ones that will delay the entire project if they are late or delayed. 14. PERT stands for ______________. 15. Project crashing can be performed using a ______________. 16. PERT can use three estimates for activity time. These three estimates are ______________, ______________, and ______________. 17. The latest start time minus the earliest start time is called the ______________ time for any activity. 18. The percent of project completion, value of work completed, and actual activity costs are used to ______________ projects.

solution : 1. e 2. C 3. A 4. D 5. B 6. C 7. B 8. A 9. B 10. B 11. A 13. Critical path (or critical) 14. program evaluation and review technique 15. linear programming model 16. optimistic, most likely, pessimistic 17. slack 18. monitor and control

12. A

Chapter 13 : Waiting Lines and Queuing Theory Models 1. Most systems use the queue discipline known as the FIFO rule. b. False 2. Before using exponential distributions to build queuing models, the quantitative analyst should determine if the service time data fit the distribution. b. False 3. In a multichannel, single-phase queuing system, the arrival will pass through at least two different service facilities. a. True 4. Which of the following is not an assumption in models? a. arrivals come from an infinite or very large population b. arrivals are Poisson distributed c. arrivals are treated on a FIFO basis and do not balk or renege d. service times follow the exponential distribution 5. A queuing system described as would have a. exponential service times. b. two queues. . d. constant arrival rates. 6. Cars enter the drive-through of a fast-food restaurant to place an order, and then they proceed to pay for the food and pick up the order. This is an example of a. a multichannel system. c. a multiqueue system. d. none of the above. 7. The utilization factor for a system is defined as a. mean number of people served divided by the mean number of arrivals per time period. b. the average time a customer spends waiting in a queue. . d. the percentage of idle time. e. none of the above.

8. Which of the following would not have a FIFO queue discipline? a. fast-food restaurant b. post office c. checkout line at grocery store 9. A company has one computer technician who is responsible for repairs on the company’s 20 computers. As a computer breaks, the technician is called to make the repair. If the repairperson is busy, the machine must wait to be repaired. This is an example of a. a multichannel system. . c. a constant service rate system. d. a multiphase system. 10. In performing a cost analysis of a queuing system, the waiting time cost is sometimes based on the time in the queue and sometimes based on the time in the system. The waiting cost should be based on time in the system for which of the following situations? a. waiting in line to ride an amusement park ride b. waiting to discuss a medical problem with a doctor c. waiting for a picture and an autograph from a rock star back in service 11. Customers enter the waiting line at a cafeteria on a firstcome, firstserved basis. The arrival rate follows a Poisson distribution, and service times follow an exponential distribution. If the average number of arrivals is 6 per minute and the average service rate of a single server is 10 per minute, what is the average number of customers in the system? a. 0.6 b. 0.9 d. 0.25 e. none of the above 12. In the standard queuing model, we assume that the queue discipline is ____________. 13. The service time in the M/M/1 queuing model is assumed to be ____________. 14. When managers find standard queuing formulas inadequate or the mathematics unsolvable, they often resort to ____________ to obtain their solutions. solution : 1. a 2. A 3. B 4. E 5. C 6. B 7. C 8. D 9. B 10. D 11. c 12. first-come, first-served 13. negative exponentially distributed 14. simulation

Chapter 14 : Simulation Modeling 1. Simulation is a technique usually reserved for studying only the simplest and most straightforward of problems. a. True 2. A simulation model is designed to arrive at a single specific numerical answer to a given problem. a. True 3. Simulation typically requires a familiarity with statistics to evaluate the results. b. False 4. The verification process involves making sure that a. the model adequately represents the real-world system. . c. the correct random numbers are used. d. enough trial runs are simulated. 5. The validation process involves making sure that b. the model is internally consistent and logical. c. the correct random numbers are used. d. enough trial runs are simulated. 6. Which of the following is an advantage of simulation? a. It allows time compression. b. It is always relatively simple and inexpensive. c. The results are usually transferable to other problems. d. It will always find the optimal solution to a problem. 7. Which of the following is a disadvantage of simulation? a. It is inexpensive even for the most complex problem. b. It always generates the optimal solution to a problem. c. The results are usually transferable to other problems. d. Managers must generate all of the conditions and constraints for solutions that they wish to examine.

8. A meteorologist was simulating the number of days that rain would occur in a month. The random number interval from 01 to 30 was used to indicate that rain occurred on a particular day, and the interval 31–00 indicated that rain did not occur. What is the probability that rain did occur? a. 0.30 b. 0.31 c.1.00 d. 0.70 9. Simulation is best thought of as a technique to a. give concrete numerical answers. b. increase understanding of a problem. c. provide rapid solutions to relatively simple problems. d. provide optimal solutions to complex problems. 10. When simulating the Monte Carlo experiment, the average simulated demand over the long run should approximate the a. real demand. b. expected demand. c. sample demand. d. daily demand. 11. The idea behind simulation is to a. imitate a real-world situation. b. study the properties and operating characteristics of a real-world situation. c. draw conclusions and make action decisions based on simulation results. d. all of the above. 12. Using simulation for a queuing problem would be appropriate if a. the arrival rate follows a Poisson distribution. b. the service rate is constant. c. the FIFO queue discipline is assumed. d. there is a 10% chance an arrival would leave before receiving service. 13. A probability distribution has been developed, and the probability of 2 arrivals in the next hour is 0.20. A random number interval is to be assigned to this. Which of the following would not be an appropriate interval?

a. 01–20 b. 21–40 c. 00–20 d. 00–19 e. all of the above

14. In a Monte Carlo simulation, a variable that we might want to simulate is a. lead time for inventory orders to arrive. b. times between machine breakdowns. c. times between arrivals at a service facility. d. number of employees absent from work each day. e. all of the above. 15. Use the following random numbers to simulate yes and no answers to 10 questions by starting in the first row and letting a. the double-digit numbers 00–49 represent yes, and 50–99 represent no. b. the double-digit even numbers represent yes, and the odd numbers represent no. Random numbers: 52 06 50 88 53 30 10 47 99 37 66 91 35 32 00 84 57 00 solution : 1. b 2. B 3. A 4. B 5. A 6. A 7. D 8. A 9. B 10. B 11. D 12. D 13. c 14. E 15. (a) no, yes, no, no, no, yes, yes, yes, no, yes...