Question

I just need the last two parts of the question answered.

PM.66 Real estate developer Russell Call was working with a few contractors to make a number of improvements to one of his rental properties. After gathering information from these contractors he determined the following durations, predecessors, and costs of all the required activities Activity Normal Time (weeks) Crashed Time (weeks) Normal Cost Crashed Cost Predecessor(s) $1,050 $2,000 $2,560 $2,600 $1,300 $2,600 $2,200 $1,800 $2,400 4 $4,200 $5,540 $2,050 4 $1,600 D, E What is the overall duration of the project? 16 Which of the following activities has the lowest crash cost per week? Which of the following activities has the highest crash cost per week? If you wanted to shorten the overall duration of the project, which activity should you crash first? What is the total cost of crashing the project from its current duration down to 13 weeks? Number What is the total cost of crashing the project from its original duration to 11 weeks? Number

Answer 1

Activity	Normal time	Crash time	Normal cost	Crash cost	Slope	Crash limit
A	3	2	$1,050	$3,200	$2,150	1
B	6	5	$2,000	$2,560	$560	1
C	3	2	$1,300	$2,600	$1,300	1
D	7	3	$2,200	$2,600	$100	4
E	6	3	$1,800	$2,400	$200	3
F	4	3	$4,200	$5,540	$1,340	1
G	4	2	$1,600	$2,050	$225	2

Slope = (Crash cost - Normal cost) / (Normal time - Crash time).

The rule of crashing is to crash the activity on the critical path which has the least slope.

Initial State Start 4 母一母 4 Project paths Duration Normal cost $14,150 Crash cost S0 A-D-G 14 $14,150 16 Total cost B-E-G C-F Project duration 16

Step-1: Crash E by 2 weeks 7 End Start 4 4 4 Project paths Duration $14,150 Normal cost Crash cost $400 A-D-G 14 Total cost B-E-G 14 $14,550 C-F Project duration 14

Step-2: Crash G by week Start End 4 4 Project paths Duration $14,150 Normal cost A-D-G 13 Crash cost $625 13 Total cost $14,775 B-E-G C-F Project duration 13

So,

Cost of crashing the project to 13 weeks is $625 and the total cost is $14,775 (Choose the answer that is desired, the language is twisted, i.e. whether they want the total cost or just the cost of crashing is not very clear).

Step-3: Crash G by week End Start 4 4 Project paths Duration $14,150 Normal cost Crash cost $850 A-D-G 12 $15,000 Total cost B-E-G 12 C-F Project duration 12

Step-4: Crash D and E by 1 week each Start End 4 Project paths Duration $14,150 Normal cost Crash cost $1,150 $15,300 A-D-G Total cost B-E-G C-F Project duration 11

So,

Cost of crashing the project to 11 weeks is $1,150 and the total cost is $15,300 (Choose the answer that is desired, the language is twisted, i.e. whether they want the total cost or just the cost of crashing is not very clear).