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Test #3 Review Problem 6-8, page 254 in the textbook: A marketing firm is planning to conduct a survey of a segment of the potential product audience for one of its customers. The planning process for preparing to conduct the survey consists of six activities with procedure relationships and activity time estimates given below: a. Determine all paths through the network from node 1 to node 6 and the duration of each, and indicate the critical path. b. Determine the earliest and latest activity start and finish times. c. Determine the slack for each activity. Activity Immediate Immediate Activity Early Early Late Late Critical No Description Predecessors Successors Time Start Finish Start Finish Slack Path

1 Determine survey objectives --- 2,3 3 0 3 0 3 0 1 2 Select and hire personnel 1 4 3 3 6 5 8 2 3 Design questionnaire 1 4,5 5 3 8 3 8 0 3 4 Train personnel 2,3 6 4 8 12 8 12 0 4 5 Select target audience 3 6 3 8 11 9 12 1

6 Make personnel assignments 4,5 --- 2 12 14 12 14 0 6

Project Completion Time 14 days

Path Time 1-2-4-6 12 1-3-5-6 13

1

2

3

4

5

6

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Problem 6-17, page 256 in the textbook: The Stone River Textile Mill was inspected by OSHA and found to be in violation of a number of safety regulations. The OSHA inspectors ordered the mill to alter some exiting machinery to make it safer (e.g., add safety guards); purchase some new machinery to replace older, dangerous machinery; and relocate some machinery to make safer passages and unobstructed entrances and exists. OSHA gave the mill only 35 weeks to make the changes; if the changes were not made by then, the mill would be fined $300,000. The mill determined the activities in a project network that would have to be completed and then estimated the indicated activity times, as shown below. Determine the following: a. Expected activity times b. Critical path activities (given activity slacks) and their variances c. Expected project duration, variance, and standard deviation. d. The probability that the mill will be fined $300,000

Activity Immediate Immediate Optimistic Most Likely Pessimistic Mean Critical

No Description Predecessors Successors Time Est Time Est Time Est Time Slack Path Variance

1 Order new machinery --- 4,5 1 2 3 2.0 7.3 0.11

2 Plan new physical layout --- 6 2 5 8 5.0 0.0 2 1.00

3 Determine safety changes in existing machinery --- 7 1 3 5 3.0 8.7 0.44

4 Receive equipment 1 8,9,10 4 10 25 11.5 7.3 12.25

5 Hire new employees 1 8,9,10 3 7 12 7.2 11.7 2.25

6 Make plant alterations 2 9,10 10 15 25 15.8 0.0 6 6.25

7 Make changes in existing machinery 3 10 5 9 14 9.2 8.7 2.25

8 Train new employees 4,5 11 2 3 7 3.5 9.2 0.69

9 Install new machinery 4,5,6 11 1 4 6 3.8 1.5 0.69

10 Relocate old machinery 4,5,6,7 11 2 5 10 5.3 0.0 10 1.78

11 Conduct employee safety orientation 8,9,10 --- 2 2 2 2.0 0.0 11 0.00

Expected Time 28.2 weeks

Project Variance 9.03

Project Standard Deviation 3.00 weeks

Probability project will last > 35 weeks is 0.0115

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Problem 7-3, page 313 in the textbook: Oranges are grown, picked, and then processed and packaged at distribution centers in Tampa, Miami, and Fresno. These centers supply oranges to markets in New York, Philadelphia, Chicago, and Boston. The table below shows the demand, supply, and shipping costs per truckload ($100s). Find the amounts to be shipped between DCs and markets at the lowest cost. Grain Orange Orange Markets Shipped Growers New York Phili Chicago Boston Supply From Tampa 130 70 0 0 200 200 Miami 0 50 100 0 150 150 Fresno 0 50 0 150 200 200 Demand 130 170 100 150

Grain Shipped

To 130 170 100 150

Total Cost $4,700

Transportation Costs Per Truckload

($100s) From\To New York Phili Chicago Boston Tampa $9 $14 $12 $17 Miami $11 $10 $6 $10 Fresno $12 $8 $15 $7