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NETWORKS, FUR2 2020 VCAA 5

The Sunny Coast cricket clubroom is undergoing a major works project.

This project involves nine activities: to .

The table below shows the earliest start time (EST) and duration, in months, for each activity.

The immediate predecessor(s) is also shown.

The duration for activity is missing.
 

   

The information in the table above can be used to complete a directed network.

This network will require a dummy activity.

  1. Complete the following sentence by filling in the boxes provided.    (1 mark)

    This dummy activity could be drawn as a directed edge from the end of activity to the start of activity  
  1. What is the duration, in months, of activity  ?   (1 mark)

  2. Name the four activities that have a float time.   (1 mark)

  3. The project is to be crashed by reducing the completion time of one activity only.

     

    What is the minimum time, in months, that the project can be completed in?    (1 mark)

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a.   

♦♦ Mean mark part (a) 26%.
   

b.   

♦ Mean mark part (b) 49%.

 


  

c.   

♦♦ Mean mark part (c) 23%.


  

d.   

♦♦♦ Mean mark part (d) 12%.

NETWORKS, FUR1 2019 VCAA 7 MC

A project involves nine activities, to .

The immediate predecessor(s) of each activity is shown in the table below.
 

             Activity            Immediate
     predecessor(s)     
 
 
 
 
 
 
 
 
 

 
A directed network for this project will require a dummy activity.

The dummy activity will be drawn from the end of

  1. activity to the start of activity .
  2. activity to the start of activity .
  3. activity to the start of activity .
  4. activity to the start of activity .
  5. activity to the start of activity .
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NETWORKS, FUR1 2011 VCAA 7 MC

Andy, Brian and Caleb must complete three activities in total (K, L and M)

The table shows the person selected to complete each activity, the time it will take to complete the activity in minutes and the immediate predecessor for each activity.
 

   

 
All three activities must be completed in a total of 40 minutes.

The instant that Andy starts his activity, Caleb gets a telephone call.

The maximum time, in minutes, that Caleb can speak on the telephone before he must start his allocated activity is

A.    5

B.   13

C.   18

D.   24

E.   34

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♦♦ Mean mark 33%.
MARKER’S COMMENT: Many students incorrectly answered the earliest starting time, C.

NETWORKS, FUR2 2006 VCAA 3

The five musicians are to record an album. This will involve nine activities.

The activities and their immediate predecessors are shown in the following table.

The duration of each activity is not yet known.
 

NETWORKS, FUR2 2006 VCAA 31
 

  1. Use the information in the table above to complete the network below by including activities ,  and .  (2 marks)

     

NETWORKS, FUR2 2006 VCAA 32

There is only one critical path for this project.

  1. How many non-critical activities are there?   (1 mark)

The following table gives the earliest start times (EST) and latest start times (LST) for three of the activities only. All times are in hours.


Networks, FUR2 2006 VCAA 3_3

  1. Write down the critical path for this project.   (1 mark)

The minimum time required for this project to be completed is 19 hours.

  1. What is the duration of activity ?   (1 mark)

The duration of activity is 3 hours.

  1. Determine the maximum combined duration of activities and .   (1 mark) 
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  1.  
    networks-fur2-2006-vcaa-3-answer
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a.    networks-fur2-2006-vcaa-3-answer

 

b.  

 

c.   

♦ Mean mark of parts (c)-(e) (combined) was 36%.

 

d.   
   

 

e.  

NETWORKS, FUR1 2015 VCAA 9 MC

The table below shows, in minutes, the duration, the earliest starting time (EST) and the latest starting time (LST) of eight activities needed to complete a project.
 

NETWORKS, FUR1 2015 VCAA 9 MC

 
Which one of the following directed graphs shows the sequence of these activities?

NETWORKS, FUR1 2015 VCAA 9 MCabcde

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NETWORKS, FUR2 2013 VCAA 2

A project will be undertaken in the wildlife park. This project involves the 13 activities shown in the table below. The duration, in hours, and predecessor(s) of each activity are also included in the table.
 
NETWORKS, FUR2 2013 VCAA 21
 

Activity is missing from the network diagram for this project, which is shown below.

 
NETWORKS, FUR2 2013 VCAA 22
 

  1. Complete the network diagram above by inserting activity .   (1 mark)

  2. Determine the earliest starting time of activity .   (1 mark)

  3. Given that activity is not on the critical path:
    i.     Write down the activities that are on the critical path in the order that they are completed.   (1 mark)

  4. ii. Find the latest starting time for activity .   (1 mark)

  5. Consider the following statement.
     
    ‘If just one of the activities in this project is crashed by one hour, then the minimum time to complete the entire project will be reduced by one hour.’

    Explain the circumstances under which this statement will be true for this project.   (1 mark)

  6. Assume activity is crashed by two hours.

    What will be the minimum completion time for the project?   (1 mark) 

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  1.  
    networks-fur2-2013-vcaa-2-answer
  3. i.
    ii.

Show Worked Solution
a.    networks-fur2-2013-vcaa-2-answer

 

b.   
   

 

c.i.   

♦♦ Mean mark of parts (c)-(e) (combined) was 40%.

 

c.ii.  networks-fur2-2013-vcaa-23-answer

  
d.  

MARKER’S COMMENT: Most students struggled with part (d).


  

e.  

NETWORKS, FUR2 2010 VCAA 4

In the final challenge, each of four teams has to complete a construction project that involves activities to .
 

NETWORKS, FUR2 2010 VCAA 4
 

Table 1 shows the earliest start time (EST), latest start time (LST) and duration, in minutes, for each activity. 

The immediate predecessor is also shown. The earliest start time for activity is missing.

  1. What is the least number of activities that must be completed before activity can commence?   (1 mark)

  2. What is the earliest start time for activity ?   (1 mark)

  3. Write down all the activities that must be completed before activity can commence.   (1 mark)

  4. What is the float time, in minutes, for activity ?   (1 mark)

  5. What is the shortest time, in minutes, in which this construction project can be completed?   (1 mark)

  6. Write down the critical path for this network.   (1 mark)

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a.  
  

b.   
   

  
c.   
  

d.   
   

 

e.  

 

f.  

NETWORKS, FUR2 2011 VCAA 3

A section of the Farnham showgrounds has flooded due to a broken water pipe. The public will be stopped from entering the flooded area until repairs are made and the area has been cleaned up.

The table below shows the nine activities that need to be completed in order to repair the water pipe. Also shown are some of the durations, Earliest Start Times (EST) and the immediate predecessors for the activities.
 

NETWORKS, FUR2 2011 VCAA 3 

  1. What is the duration of activity ?   (1 mark)

  2. What is the Earliest Start Time (EST) for activity ?   (1 mark)

  3. Once the water has been turned off (Activity ), which of the activities to could be delayed without affecting the shortest time to complete all activities?   (1 mark)

It is more complicated to replace the broken water pipe (Activity ) than expected. It will now take four hours to complete instead of two hours.

  1. Determine the shortest time in which activities to can now be completed.   (1 mark)

Turning on the water to the showgrounds (Activity ) will also take more time than originally expected. It will now take five hours to complete instead of one hour.

  1. With the increased duration of Activity and Activity , determine the shortest time in which activities to can be completed.   (1 mark)

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a.   
   
♦ Mean mark of all parts (combined) was 42%.

  
b.  

  
c.   

MARKER’S COMMENT: Many students incorrectly included in this answer (note that is not on the critical path).

  
d.  


  

e.