Multiple Choice: (select the most correct response)

1. In the maturity stage of a product’s life cycle, a typical operations strategy would  be:

a. Increasing capacity.
b. Short production runs.
c. Cost minimization.
                  d.   Increases in process stability.

2. Which statement is true?

a. The mission statement precedes analysis of external and
internal factors.
b. Market segments are selected prior to development of the
mission statement.
c. Functional strategy is formulated prior to corporate strategy.
d. The marketing functional strategy dictates the products and
services that the firm will offer.

3. Product innovation rates are a(an):

a. A goal-based measure.
b. A corporate goal.
c. A productivity measure.
d. An external factor.

4.  Supplier reliability is a(an):

a.  A goal-based measure.
b.  A functional strategy.
c.  An internal factor.
d.  An external factor.

5.  In the production of goods, as opposed to services:
                
a. The customer may be directly involved.
b. The facility should be near the customer.
c. Quality standards are precisely measured.
d. Production scheduling focuses on customer demand rate.

6. Assume that we are using a waiting line model to analyze the number of service technicians needed to maintain machines in a factory. Our goal should be to:

a. Maximize productivity of the technicians.
b. Minimize the number of machines needing repair.
c. Minimize the downtime for individual machines.
d. Minimize the percent of idle time of the technicians.
e. Minimize the total cost ( maintenance plus downtime).

7. Which of the following is NOT true about arrivals?

a. Random arrivals are independent of each other.
b. Random arrivals cannot be predicted exactly.
c. The Poisson distribution is often used to represent the arrival pattern.
d. Service times often follow the negative exponential distribution.
e. The exponential distribution is often used to represent the arrival pattern.

8. The customer who arrives at a bank, sees a long line, and leaves is:

a. Balking.
b. Cropping.
c. Reneging.
d. Indeterminate.
e. None of the above.

9. Lines at banks where customers wait for teller windows are usually repre-sentative of a:

a. Single-channel, multiphase system.
b. Single-channel, single-phase system.
c. Multichannel, multiphase system.
d. Multichannel, single-phase system.
e. None of the above.

10.     A specialty restaurant has developed a single drive-through window. Customers order, pay, and pick up their food at the same window. Arrivals follow a Poisson distribution, while service times follow an exponential distribution. If the average number of arrivals is six (6) per hour and the service rate is two (2) every fifteen (15) minutes, what is the average number of customers in the system?

a.   0.50
b.   4.00
c.   2.25
d.   3.00
e.   None of the above

11. Given the problem statement in question 10, what is the average number of customers waiting in line behind the person being served?

a. 0.50
b. 0.75
c. 2.25
d. 3.00
e. None of the above

12. Given the problem statement in question 10, what proportion of the time is the server busy?

a. 0.25
b. 0.50
c. 0.75
d. 2.25
e. 3.00

13. Given the problem statement in question 10, how much time will elapse (in hours) from the time a customer enters the line until he/she leaves the restaurant?

a. 0.50
b. 0.25
c. 0.75
d. 2.25
e. 3.00

14. At a local fast-food joint, cars arrive randomly at a rate of 12 every 30 minutes. It takes an average of 2 minutes to serve each arrival.  The utilization factor for this system is:

a. 0.467
b. 0.547
c. 0.800
d. 0.133
e. None of the above

15. Given the problem statement in question 14, what is the average time in the queue for each arrival?

a. 2 minutes.
b. 4 minutes.
c. 6 minutes.
d. 8 minutes.
e. 10 minutes.

16. A business has three (3) fax machines. The toner in each machine needs to be changed after about five (5) hours of use. There is one (1) secretary who is responsible for the fax machine maintenance. It takes the secretary fifteen (15) minutes to replace the toner cartridge. What is the probability that two (2) fax machines need toner at the same time? (select closest value)

a. .0130
b. .0909
c. .1286
d. .1415
e. .8576

17. A single automatic carwash with one bay and a cycle time of 2.5 minutes is what type of model?

a. M/M/1
b. M/M/2
c. M/D/2
d. M/D/1
e. M/G/1

18. The utilization factor is defined as the:

a. Percent of  time the system is idle.
b. Average percent of time the customers wait in line.
c. Average time the service system is open.
d. Average length of the service line.
e. None of the above

19. In queuing analysis, total expected cost is the sum of expected_______plus expected_________.

a. service costs, arrival costs
b. facility costs, calling costs
c. calling costs, inventory costs
d. calling costs, waiting costs
e. service costs, waiting costs

20. Commonly obtained measures of a queuing system’s performance include:

a. Average time each customer spends in the system, and the probability that the service system will be idle.
b. The average queue length, and the maximum time a customer may spend in the queue.
c. Maximum queue length, and the probability of a specific number of customers in the system.
d. Average queue length, and the probability that the waiting time will exceed a specified period.

21. A maintenance shop employing one (1) mechanic and servicing fifty (50) machines would be described as a:

a. Single-channel, priority system
b. Multi-channel, infinite calling population system
c. Single-channel, finite calling population system
d. Multi-channel, finite calling population system

22. The service facility is a combination of:

a. Arrival rates and service rates
b. Servers and customers
c. Queue length and queue discipline
d. Channels and phases

TRUE or FALSE ( select the one correct response )

23.  In queuing theory, the theoretical frequency distribution of system arrivals must be statistically identical to the observed frequency distribution of system arrivals.

                                              TRUE            FALSE

24. The most common queuing models assume a service rate that is normally distributed.

                                              TRUE            FALSE

25. In a restaurant, the average time spent in the system is the time between a customer’s arrival and departure.

                                              TRUE            FALSE

26. Given a value for ‘lambda’ ( λ ) , a theoretical frequency distribution for system arrivals can be identified.
                                      
                                              TRUE            FALSE

27. All queuing systems only exhibit first-in, first-out queue discipline.

                                              TRUE            FALSE
TRUE or FALSE

28.  T  F  It is impossible to develop a process that has zero variability.

29.  T  F  Assignable variations in a process are also called natural variations.

30.  T  F  An x-bar chart would be appropriate to monitor the number of defects in
                a production lot.

31.  T  F  The central limit theorem provides the statistical foundation for control
                charts.

32.  T  F  If we are tracking quality of performance for a class of students, we should
                plot the pass/fail result on a p-chart.

33.  T  F  Sample sizes of  4 or 5 can be used when building x-bar and R-control charts.

34.  T  F  If we are attempting to control the diameter of bowling balls, we will find
                a  p-chart to be quite helpful.

35.  T  F  A c-chart would be appropriate to monitor the number of weld defects on
                the steel plates of a ship’s hull.

MULTIPLE CHOICE

36.  Bags of pretzels are sampled to ensure proper weight. The overall average for the
       samples is nine (9) ounces. Each sample contains 25 bags. The standard deviation
       is estimated to be three (3) ounces. The upper control chart limit ( for 99.7% confi-
       dence ) for the average would be____ounces.

       a.    9.4
       b.  18.0
       c.  10.2
       d.    7.2
       e.  10.8

37.  R-charts measure changes in:

       a.  central tendency.
       b.  degree of variation.
       c.  number of defects per production lot.
       d.  natural variations.
       e.  none of the above.

38.  Bags of chocolate candy are sampled to ensure proper weight. The overall average
       for the samples is 36 ounces. Each sample contains twelve bags. The average range
       is 1.3 ounces. The upper control chart limit for the average would be:

       a.  36.3458
       b.  35.6542
       c.  38.3101
       d.  36.6279
       e.  37.1258

39.  Bags of tea are sampled to ensure proper weight. The overall average for the samples
       is  8 ounces. Each sample contains 10 bags. The average range is 0.1 ounces. What is
       the lower limit of the average chart?

       a.  7.9692
       b.  8.0308
       c.  7.9076
       d.  8.0924
       e.  8.1024

40.  The average range of a process for packaging cereal is 1.1 ounces. If the sample size
       is ten (10) , find the upper control chart limit for the range chart.

       a.  0.245
       b.  1.955
       c.  1.777
       d.  0.223
       e.  0.143

41.  Given the problem statement in question 40, find the lower control chart limit for the
       range chart.

       a.  0.245
       b.  1.955
       c.  1.777
       d.  0.223
       e.  0.143

42.  Defects in computer hard-drives will usually render the entire computer worthless.
       For a particular model, the percent defective in the past has been 1%.  If a sample
       size of 400 is taken, what would the 95.5% lower control chart limit be?

       a.  0.00995
       b.  0.00005
       c.  0.00000
       d.  0.01000
       e.  0.09550

43.  Defects in marble countertops usually require the whole top to be reconstructed.
       In one kitchen shop, the percent defective in the past has been one (1) percent.
       If a sample size of 30 is taken, what should be the 95.5% percent upper control
       limit?

       a.  0.030
       b.  0.000
       c.  0.046
       d.  0.064
       e.  0.074

44.  A firm has been receiving complaints about the attitude of some sales clerks. Over a
       10-day period, the total number of complaints was 360.  The firm wishes to develop
       a control chart for the number of complaints. What would the upper control limit on
       the number of complaints per day be for a 3 sigma ( 99.7% ) control chart?

       a.  18
       b.  36
       c.  42
       d.  54
       e.  62

45.  Given the same problem statement above, the total number of complaints is now 250.
       What would  the lower control limit on the number of complaints per day  be for a
        3 sigma ( 99.7% ) control chart?

        a.    20
        b.      0
        c.    15
        d.    10
        e.   202.6

46.  Who introduced control charts in 1924?

        a.  W. Edwards Deming.
        b.  Philip Crosby.
        c.  J.M. Juran.
        d.  Walter Shewhart.
        e.  Malcolm Baldrige.

47.  To guarantee that cans of soda are properly filled, some cans are sampled and the
       amounts measured. The overall average for the samples is 12 ounces. Each sample
       contains 10 cans. The average range is 0.4 ounces. The lower control chart limit
       for the average would be:

       a.  12.1232
       b.  11.8768
       c.  13.2000
       d.  12.3080
       e.  11.5500

48.  The control chart:

       a.  focuses on the time dimension of a system.
       b.  captures the natural variability in the system.
       c.  can be used for categorical, discrete, or continuous variables.
       d.  all of the above.

49.  Which of the following situations suggests a process that appears to be operating
        in a state of statistical control?

        a.  a control chart with a series of consecutive points that are above the center line
             and a series of consecutive points that are below the center line.
        b.  a control chart in which no points fall outside either the upper control limit or
             the lower control limit, and no patterns are present.
        c.  a control chart in which several points fall outside the upper control limit.
        e.  all of the above.

50.  A political pollster randomly selects a sample of 100 voters each day for 8 successive
       days and asks how many will vote for the incumbent.
       The pollster wishes to construct a ‘p’ chart to see if the percentage favoring the in-
       cumbent candidate is too eratic.

                                   Sample (Day)         Number Favoring Incumbent
                                            
                                             1                                          57
                                             2                                          57
                                             3                                          53
                                             4                                          51
                                             5                                          55
                                             6                                          60
                                             7                                          56
                                             8                                          59

       What is the numerical value of the center line for the ‘p’ chart?

        a.  0.53
        b.  0.56
        c.  0.63
        d.  0.66

51.  Given the problem statement above, what is the numerical value of the lower control
        limit for the ‘p’ chart?

        a.  0.37
        b.  0.41
        c.  0.50
        d.  0.71

MULTIPLE CHOICE

52.  Which of the following statements about the shortest route method is true?

      a.  each arc in the network must represent distance.
      b.  the solution procedure begins at the network destination.
      c.  the initial member of the permanent set is the origin.
      d.  the backtracking phase determines the minimum distance between the origin
           and each node in the network.
     
     
53.  All the nodes must be connected in which of the following techniques?

     a.  minimal-flow.
     b.  maximal-spanning tree.
     c.  shortest-route.
     d.  maximal-flow.
     e.  minimal-spanning tree.

54.  Given the following distances between destination nodes, what is the minimum
       distance that connects all the nodes?

                                      From         To           Distance
                                          1              2                 300
                                          2              3                 150
                                          1              3                 200

      a.  450
      b.  150
      c.  350
      d.  650
      e.  none of the above.

55.  Given the following distances between destination nodes, what is the minimum
       distance that connects all the nodes?

                                      From       To           Distance

                                          1            2                 100
                                          1            3                 200
                                          2            3                 100
                                          2            4                 150
                                          2            5                 200
                                          3            4                 150
                                          3            5                 300
                                          4            5                 250
                                          4            6                 200
                                          5            6                 100

      a.    900
      b.    650
      c.    400
      d.  1200
      e.  none of the above.

56.  Find the shortest-route from Node 1 to Node 6 :

                          From Node      To Node      Distance
                                  1                     2                 150
                                  1                     3                 200
                                  2                     3                 100
                                  2                     4                 200
                                  2                     5                   50
                                  3                     4                 350
                                  3                     5                 300
                                  4                     6                 100
                                  5                     6                 100

      a.  300
      b.  450
      c.  550
      d.  650
      e.  none of the above.

57. In network models, the lines connecting the nodes are called:

      a.  bridges.
      b.  arrows.
      c.  spans.
      d.  arcs.
      e.  links.

58. The minimal-spanning technique ( minimal spanning tree ) would best be used:

a. to assign workers to jobs in the cheapest manner.
b. to determine LAN network wiring within a building.
c. to minimize traffic flow on a busy highway.
d. by a trucking firm making frequent but repeatable drops.
e. to determine the number of units to ship from each source to each destination.

59.  Find the shortest route from Node 1 to Node 4:

                                    From Node         To Node        Distance

                                           1                         2                   250
                                           1                         3                   400
                                           1                         4                   600
                                           2                         3                     50
                                           2                         4                   300
                                           3                         4                   200

a. 750
b. 500
c. 550
d. 600
e.   50

TRUE or FALSE ( select the one correct response )

60.  T   F    In the minimal-spanning tree technique, it is necessary to start at the last node in the network.

61.  T   F   In the minimal-spanning tree technique, if there is a tie for the nearest node, that suggests that there may be more than one optimal solution.

62.  T   F   In minimal spanning-tree and shortest-route models, the points on the network are refrerred to as ‘nodes’.

63.  T   F   The minimal-spanning tree technique and the shortest-route technique obtain the same optimal solution.

64.  T   F   The shortest-route technique finds the maximum flow of any quantity or substance through a network.