Case 1: Systems Analysis I

Assigned: 14 September 2004
Due: 16 September 2004 (in class)

You and several friends are about to prepare a lasagne dinner. The tasks to be performed, their time (in minutes), and the precedence constraints are as follows:

Task # Task
Time
Tasks that precede
0 Pull out the receipe
5
-
1 Buy mozzarella cheese
30
0
2 Slice mozzarella cheese
5
1
3 Beat 2 eggs
2
0
4 Mix eggs and ricoto cheese
3
3
5 Cut onions and mushrooms
7
0
6 Cook tomato sauce
25
5
7 Boil water
15
0
8 Boil noodles
10
7
9 Drain noodles
2
8
10 Assemble all ingredients
10
9,6,4,2
11 Preheat oven
15
0
12 Bake the lasagne
30
10,11
  1. Create a PERT network for this problem.
  2. Identify the early start, early finish, late start, late finish, and slack for each Task.
  3. Identify the critical path.

Using the instructions for downloading project management software found on the Wiki site, do the following:

  1. Create a Gantt chart.
  2. Create a PERT network, and highlight the critical path.
  3. Because of a phone call you were interrupted for 6 minutes when you should have been cutting onions and mushrooms. By how much will the dinner be delayed? If you use your food processor, which reduces the cutting time from 7 minutes to 2 minutes for cutting onions and mushrooms, will the dinner be delayed (assume that you were still interrupted by the phone call)?