Question 1

Given the tasks, estimated durations, and crash costs shown below, if the benefit to crash the project by each day is a maximum of $750, how many days would it be worthwhile to crash the project? 
A)0
B)1
C)2
D)3
E)4

Accepted Answer

The cost to crash the second day is $800, so the benefit would not justify the cost.

Question 2

The customer has offered a $10,000 bonus if the project is completed within 14 days. What is the probability that the bonus will be earned?
A)Approximately 85 percent
B)Approximately 5 percent
C)Approximately 2.3 percent
D)Approximately 97.7 percent

Accepted Answer

t_path= 8.5 + 4.5 + 5.0 = 18 daysStandard deviation of the path = Square root of (2.25 + 1.36 + .444) = 2.01For completion within 20 days: z = (20 - 18)/2.01 = 0.995. From a standard normal

Question 3

A simple sequential project (each task must be completed before the next one can begin) has the time estimates (in days) shown below:  What is the likelihood the project will be completed in 10 days?
A)Between 88 and 88 percent
B)Between 89 and 92 percent
C)Between 93 and 98 percent
D)Between 99 and 100 percent

Accepted Answer

Standard deviation of the path = square root of the sum of the tasks' standard deviation squared = square root of (.1089 + .0289 + .0289 + .0289 + .0289 + .1089) = square root of .3334 = .577Therefore z = (10 - 9)/.577 = 1.733, and from a standard normal

Question 4

Annie is planning a large surprise party for her sister Gwendolyn. She has developed the following plan, including estimates of the time (in hours) and cost necessary to perform each of the tasks required.  What is the planned duration of the preparation for the surprise party, assuming the critical path is completed?
A)16 hours
B)8 hours
C)20 hours
D)30 hours

Accepted Answer

The critical path is A, D, E, F at 20 hours. Path AB is 10 hours. Path AC is 16 hours.

Question 5

A project manager has discovered that three tasks are on the critical path for a particular project. She has developed the time estimates (in days) shown in the table below. Complete the table and determine the expected completion time for the project. 
A)17 days
B)18 days
C)21 days
D)19 days

Accepted Answer

Expected completion time for the project is 18 days.

Question 6

Given the project data below, what is the expected length of path A, B, C? 
A)9.0
B)9.8
C)9.4
D)17

Accepted Answer

Expected duration for each task is (B + 4ML + W)/6. Sum up the three expected values to get the expected value for the path.

Question 7

In evaluating time-cost trade-offs, we start by crashing the task on the critical path that:
A)Has the lowest cost to reduce by one unit of time.
B)Has the lowest total crash cost.
C)Can be reduced the most.
D)Is the longest.
E)None of the these.

Accepted Answer

Crashing begins by reducing the task that has the lowest cost to reduce by one unit of time in the project.

Question 8

Annie is planning a large surprise party for her sister Gwendolyn. She has developed the following plan, including estimates of the time (in hours) and cost necessary to perform each of the tasks required.  What is Annie's total benefit from crashing this project?
A)$55
B)$185
C)$160
D)$240

Accepted Answer

Savings from crashing:Crash E by 2 hours at a cost of $75 and a benefit of $80. Net benefit: $5.The total cost of crashing A and E is $185, and the total benefit is $240. The net benefit is $240 - $185 = $55.

Question 9

Given the tasks, estimated durations, and crash costs shown below, what is the total cost of the steps needed to provide the cheapest way to reduce the project length by three days? 
A)$2,800
B)$2,500
C)$1,100
D)$2,300

Accepted Answer

Crash both B and C one day, then D one day, then A one day.

Question 10

Task X has a best-case duration of 4 days, a worst-case duration of 10 days, and a most likely duration of 6 days. Using this information, we can estimate a 50 percent probability that the task will be completed in no more than how many days?
A)6.0 days
B)3.3 days
C)10.0 days
D)6.3 days

Accepted Answer

Expected time is the time for which there is a 50 percent chance that the task will be completed at that time or earlier. Expected time = (4 + 4 × 6 + 10)/6 = 6.3 days.

Question 11

A simple sequential project (each task must be completed before the next one can begin) has the time estimates (in days) shown below:  What is the probability that the project shown in Exhibit 15S-5 will be completed within 8.5 days? (Choose the closest answer.)
A)80 percent
B)20 percent
C)75 percent
D)5 percent

Accepted Answer

z = (8.5 - 9)/.577 = -0.5/.577 = 0.867. F(z) = approximately 0.80 and 1 - F(z) = approximately 20 percent.

Question 12

Annie is planning a large surprise party for her sister Gwendolyn. She has developed the following plan, including estimates of the time (in hours) and cost necessary to perform each of the tasks required.  Annie will save $40 for every hour she can reduce from her plan. Annie has decided to crash her project and use the money she saves to purchase a larger gift for Gwendolyn. Which task should she crash first?
A)A
B)D
C)C
D)E
E)B

Accepted Answer

The critical path is A, D, E, F at 20 hours. Path AB is 10 hours. Path AC is 16 hours. Activity A has the lowest crash cost of the activities on the critical path.

Question 13

Annie is planning a large surprise party for her sister Gwendolyn. She has developed the following plan, including estimates of the time (in hours) and cost necessary to perform each of the tasks required.  If Annie crashes only the task identified in the previous problem, but crashes it to its minimum duration, how much will she save on the project?
A)$55
B)$185
C)$160
D)$50

Accepted Answer

Crash A by 4 hours at a cost of $110 and a benefit of $160 (4 * $40). Net benefit: $50.

Question 14

Annie is planning a large surprise party for her sister Gwendolyn. She has developed the following plan, including estimates of the time (in hours) and cost necessary to perform each of the tasks required.  Annie turns her attention to crashing another task in her project. If she wants to benefit even more, what is the next task to crash?
A)A
B)C
C)E
D)F

Accepted Answer

Task E has the next lowest crash cost per hour on the critical path.

Question 15

An estimate of the duration of a task that is based on a weighted average of a range of possible task durations is known as:
A)Most likely duration.
B)Expected duration.
C)Worst-case duration.
D)Probabilistic duration.

Accepted Answer

Expected duration is the outcome of the weighted average of best-case, worst-case, and most likely case durations.

Question 16

A simple sequential project (each task must be completed before the next one can begin) has the time estimates (in days) shown below:  What is the expected total time for the path?
A)7.33 days
B)9.00 days
C)10 days
D)12.67 days

Accepted Answer

In this problem, the expected durations for each task will all be equal to the most likely durations since the worst case and best case are an equal distance from the most likely case.

Question 17

Given the project data below, what is the standard deviation of durations for path A, B, C?" 
A)1.4
B)2.3
C)1.7
D)None of the choices is correct

Accepted Answer

Standard deviation for each task is (Worst case - Best case)/6. Square each standard deviation, sum them up, and take the square root to get the standard deviation for the path.

Question 18

Which of the following statements best describes "crash cost"?
A)Estimated cost to reduce a project task duration by one time unit.
B)Estimated cost to reduce a project duration by one time unit.
C)Estimated cost to reduce the project schedule by one time unit.
D)Actual cost to reduce a project duration by one time unit.
E)Actual cost to change a project schedule.

Accepted Answer

Crash cost is the estimated cost to reduce a given task; it may or may not reduce the project length, depending on other factors.

Question 19

Which of the following statements is true regarding crash costs?
A)Crash costs tend to increase with each additional day of crashing.
B)Crash costs tend to decrease with each additional day of crashing.
C)It is usually cheaper to crash tasks that are not on the critical path.
D)Additional crash costs are rarely justified in practice.

Accepted Answer

Crash costs increase for several reasons, one of which is that as multiple paths become critical, multiple tasks must be crashed in order to reduce the project an additional time unit.

Question 20

A project manager has discovered that three tasks are on the critical path for a particular project. She has developed the time estimates (in days) shown in the table below. Complete the table and determine the expected completion time for the project. 
A)Approximately 92 percent
B)Approximately 88 percent
C)Approximately 75 percent
D)Approximately 84 percent

Accepted Answer

Probability is approximately 84 percent.

Quiz 15: Extension: Advanced Methods for Project Scheduling

Given the tasks, estimated durations, and crash costs shown below, if the benefit to crash the project by each day is a maximum of $750, how many days would it be worthwhile to crash the project?

The customer has offered a $10,000 bonus if the project is completed within 14 days. What is the probability that the bonus will be earned?

A simple sequential project (each task must be completed before the next one can begin) has the time estimates (in days) shown below: What is the likelihood the project will be completed in 10 days?

A project manager has discovered that three tasks are on the critical path for a particular project. She has developed the time estimates (in days) shown in the table below. Complete the table and determine the expected completion time for the project.

Given the project data below, what is the expected length of path A, B, C?

In evaluating time-cost trade-offs, we start by crashing the task on the critical path that:

Annie is planning a large surprise party for her sister Gwendolyn. She has developed the following plan, including estimates of the time (in hours) and cost necessary to perform each of the tasks required. What is Annie's total benefit from crashing this project?

Given the tasks, estimated durations, and crash costs shown below, what is the total cost of the steps needed to provide the cheapest way to reduce the project length by three days?

Task X has a best-case duration of 4 days, a worst-case duration of 10 days, and a most likely duration of 6 days. Using this information, we can estimate a 50 percent probability that the task will be completed in no more than how many days?

A simple sequential project (each task must be completed before the next one can begin) has the time estimates (in days) shown below: What is the probability that the project shown in Exhibit 15S-5 will be completed within 8.5 days? (Choose the closest answer.)

An estimate of the duration of a task that is based on a weighted average of a range of possible task durations is known as:

A simple sequential project (each task must be completed before the next one can begin) has the time estimates (in days) shown below: What is the expected total time for the path?

Given the project data below, what is the standard deviation of durations for path A, B, C?"

Which of the following statements best describes "crash cost"?

Which of the following statements is true regarding crash costs?

A project manager has discovered that three tasks are on the critical path for a particular project. She has developed the time estimates (in days) shown in the table below. Complete the table and determine the expected completion time for the project.