Question

1. Develop a network drawing for Hill Construction and determine
the critical path. How long is the project expected to take?
2. What is the probability of finishing in 270 days?
3. If it is necessary to crash to 250 or 240 days, how would Hill do
so, and at what costs? As noted in the case, assume that optimistic
time estimates can be used as crash times.

Southwestern University: (A)* Southwestern University (SWU), a large state college in Stephenville, Texas, 30 miles southwest of the Dallas/Fort Worth metroplex, enrolls close to 20,000 students. In a typical town gown relationship, the school is a dominant force in the small city, with more students during fall and spring than permanent residents. A longtime football powerhouse, SWU is a member of the Big Eleven conference and is usually in the top 20 in college foot- ball rankings. To bolster its chances of reaching the elusive and long-desired number one ranking, in 2009, SWU hired the leg- endary Phil Flamm as its head coach.

Answer 1

1)

Start ole A-30 30 30 B-60 C-65 90 E-30 siss fesliso) D-55 F-0.1 so 50 G-30 H-20 (80159 J-10 600 200 1-30 K-01 12:23 L-30 2002 - critical -path A, C, D, G, H, I, L Expected time: 260 days Finish
.

Expected time:t=(a+4m+b)/6
a=optimistic
m=likely
b=pessimistic

2)

Project Variances=(total variances of activities on critical path)
=11.11+69.44+136.11+2.78+11.11+44.44+44.44
=319.43 days
Project standard deviation=SQRT(319.43)
17.87 days
Z=(270-260)/17.87
=0.56
For Z value of 0.56,the probaility of 0.71226.There is a 71.23% chance that the project will finish on 270 days.
3)

To be able to crash to 240 days we deduct 2 activities which has the minimum crash cost per day.
First to crash is activity A this has the minimun cost $1500
The duration of activity A can only be deduct by 10 days highest thus cost of $1500*10 is $ 15000.
Activity A(10 days *$1500 per day cost=$15000 total cost).
The next one to be crashed is activity which has the cost of $1900.
The duration of activity D can only be deduct by 20 days highest thus $1900*20is $38000.
Activity D(20 dasy *$1900per day cost=$38000 total cost)
The total extra cost necessary to crashg to 240 days is $53000.
total cost($15000+$38000=$53000).
TO be able to crash to 250 days we deduct 2 activities which has the minimum crash cost per day.
First to crash is activity A this has the minimun cost $1500
The duration of activity A can only be deduct by 10 days highest thus cost of $1500*10 is $ 15000.
Activity A(10 days *$1500 per day cost=$15000 total cost).
The next one to be crashed is activity which has the cost of $1900.
The duration of activity D can only be deduct by 20 days highest thus $1900*20is $38000.
Activity D(10days *1900 per day cost=$19000 total cost).
The total extra cost necessary to crashg to 250 days is $34000.
Total cost($15000+$19000=$34000)