Deck 7: Project Scheduling: Adding the Time Dimension

Question 1

A project team estimates that a work package is most likely to have a duration of 10 days. However, under the worst possible conditions pessimistic) it will take 40 days, and if conditions are ideal optimistic), it will take only 4 days. Using the PERT three-point estimation method, what is the expected time for this work package?

A) 18 days
B) 14 days
C) 6 days
D) 26.67 days
E) 42 days

Answer 1

14 days

Question 2

Which of the following types of precedence relationships is/are especially useful in fast-tracking situations?

A) Start-to-start
B) Start-to-finish
C) Finish-to-start
D) Finish-to-finish
E) A & C only
F) None of the above

Answer 2

Start-to-start

Question 3

Activity time estimates for the following project schedule have been developed using the PERT three-point time estimation method.

13.

Based on concepts presented in the text, what is the assumed likelihood Task D will be able to start at the end of Day 11?

A) 100%
B) 75%
C) 50%
D) 25%
E) 10%

Answer 3

25%

Question 4

Which of the following schedule display formats can require the use of dummy activities?

A) Bar chart
B) AON diagram
C) Gantt chart
D) AOA diagram
E) None of the above - in fact, there is no such thing as a dummy activity

Question 5

The following network shows a portion of an IT project involving programming, hardware installation, and implementation. As shown, programming and hardware installation are both estimated to be 52 days in duration. These estimates are not exact, given the uncertainty that can occur in any project environment, but they do share the same statistical distribution, with 52 as the median value.

Given what is covered in Chapter 6 regarding two tasks that merge into a common successor, what is the approximate probability that implementation can begin at the end of 52 days of concurrent work on programming and hardware installation?

A) 0%
B) 25%
C) 50%
D) 75%
E) 100%

Question 6

The following network is the basis for the next four questions:



-Assume all activities are scheduled to begin on their early start times. How much can we delay activity D without delaying the project?

A) 3 days
B) 4 day
C) 5 days
D) 6 days
E) 7 days

Question 7

The following information is the basis for the next three questions.
Jim and Carol Spalding have a crack in their waterline and need to replace it. This will require digging up the water line, replacing it, filling the hole, leveling the soil, and re-seeding the grass. The Spalding's plumber suggests that, since they have the well dug up, they should replace the foot valve in the well also. Below are the plumber's estimates of the time in hours) necessary to perform each of the activities required.
$$\begin{array} { | c | l | c | c | c | c | } \hline \text { Activity } & \text { Description } & \text { Predeces sor } & \text { Optimistic } & \text { Most Lik ely } & \text { Pessim istic } \\\hline \text { A } & \text { Digging } & - & 2 & 3 & 4 \\\hline \text { B } & \text { Replace line } & \text { A } & 1 & 1.5 & 2 \\\hline \text { C } & \text { Replace foot valve } & \text { B } & .5 & 1 & 1.5 \\\hline \text { D } & \text { Fill hole } & \text { C } & 1.5 & 2 & 5.5 \\\hline \text { E } & \text { Level soil } & \text { D } & .5 & 1 & 1.5 \\\hline \text { F } & \text { Reseed lawn } & \text { E } & .4 & .5 & .6 \\\hline \end{array}$$


-If the plumber and his crew begin working at 7:00 a.m., what time are they expected to finish?

A) 3:00 p.m.
B) 3:30 p.m.
C) 4:00 p.m.
D) 4:30 p.m.
E) 5:00 p.m.

Question 8

The following network is the basis for the next four questions:



-Assume all activities are scheduled to begin on their early start times. Circle the letter of each activity that has free float.

A) A
B) B
C) C
D) D
E) E
F) F
G) G

Question 9

Based on the table in the previous question showing time estimates for Activities A through E, which activity has a Standard Deviation of .833? Circle all that apply:

A) A
B) B
C) C
D) D
E) E

Question 10

The following software development plan is the basis for the next four questions


-The client would like to have the completed software in 37 weeks. What is the likelihood the critical path will be completed in that time frame?

A) 54%
B) 67%
C) 75%
D) 93%
E) 100%

Question 11

Which of the following is an example of a start-to-start relationship?

A) We cannot start design until five weeks after requirements definition is complete.
B) We cannot start pouring the concrete until the foundation has been completely excavated.
C) Editing cannot begin until two weeks after we have started writing the book.
D) The paving job cannot finish until we have started to put up the signs.
E) All of the above.

Question 12

The following network is the basis for the next four questions:



-Which of these is the critical path for this project schedule?

A) A-B-F-G
B) A-B-D-G
C) A-C-E-G
D) ABCDEFG
E) ABFDG

Question 13

For the next two questions, refer to the following AON diagram, with ES, LS, EF, LF and total and free float indicated for each activity:




-Calculate the TF total float) and FF free float) values - indicated by y and z - for Task C.

A) y = 4, z = 0
B) y = 0, z = 4
C) y = 0, z = 0
D) y = 4, z = 4
E) None of the above

Question 14

Which of the following is NOT a characteristic of the PERT method?

A) It assumes project activities are independent of each other and not affected by common factors.
B) Total project time T_E)) is assumed to have a normal distribution.
C) The distribution of possible times for an individual activity is described as a beta distribution.
D) Activity estimates are known and certain.
E) All of the above are characteristics of the PERT method.

Question 15

The following network is the basis for the next four questions:



-Assume all activities are scheduled to begin on their early start times. How much free float slack) does activity B have?

A) 0 days
B) 1 day
C) 2 days
D) 3 days
E) 4 days
F) 5 days

Question 16

The following information is the basis for the next three questions.
Jim and Carol Spalding have a crack in their waterline and need to replace it. This will require digging up the water line, replacing it, filling the hole, leveling the soil, and re-seeding the grass. The Spalding's plumber suggests that, since they have the well dug up, they should replace the foot valve in the well also. Below are the plumber's estimates of the time in hours) necessary to perform each of the activities required.
$$\begin{array} { | c | l | c | c | c | c | } \hline \text { Activity } & \text { Description } & \text { Predeces sor } & \text { Optimistic } & \text { Most Lik ely } & \text { Pessim istic } \\\hline \text { A } & \text { Digging } & - & 2 & 3 & 4 \\\hline \text { B } & \text { Replace line } & \text { A } & 1 & 1.5 & 2 \\\hline \text { C } & \text { Replace foot valve } & \text { B } & .5 & 1 & 1.5 \\\hline \text { D } & \text { Fill hole } & \text { C } & 1.5 & 2 & 5.5 \\\hline \text { E } & \text { Level soil } & \text { D } & .5 & 1 & 1.5 \\\hline \text { F } & \text { Reseed lawn } & \text { E } & .4 & .5 & .6 \\\hline \end{array}$$


-Carol Spalding can't bear to see her lawn all dug up so she has decided to visit her mother on the day the work is to be done. Carol wants to return home at 6:45 p.m., what is the probability the work will be complete when Carol arrives home?

A) 95%
B) 99.3%
C) 99.5%
D) 99.8%
E) 100%

Question 17

The following information is the basis for the next three questions.
Jim and Carol Spalding have a crack in their waterline and need to replace it. This will require digging up the water line, replacing it, filling the hole, leveling the soil, and re-seeding the grass. The Spalding's plumber suggests that, since they have the well dug up, they should replace the foot valve in the well also. Below are the plumber's estimates of the time in hours) necessary to perform each of the activities required.
$$\begin{array} { | c | l | c | c | c | c | } \hline \text { Activity } & \text { Description } & \text { Predeces sor } & \text { Optimistic } & \text { Most Lik ely } & \text { Pessim istic } \\\hline \text { A } & \text { Digging } & - & 2 & 3 & 4 \\\hline \text { B } & \text { Replace line } & \text { A } & 1 & 1.5 & 2 \\\hline \text { C } & \text { Replace foot valve } & \text { B } & .5 & 1 & 1.5 \\\hline \text { D } & \text { Fill hole } & \text { C } & 1.5 & 2 & 5.5 \\\hline \text { E } & \text { Level soil } & \text { D } & .5 & 1 & 1.5 \\\hline \text { F } & \text { Reseed lawn } & \text { E } & .4 & .5 & .6 \\\hline \end{array}$$


-The plumber has scheduled another small job at 6:00 p.m. If it takes 1/2 hour to drive from the Spalding's to the other job, what is the probability the plumber will be able to make the 6:00 p.m. appointment on time?

A) 63%
B) 75%
C) 89%
D) 95%
E) 99%

Question 18

For the next two questions, refer to the following AON diagram, with ES, LS, EF, LF and total and free float indicated for each activity:




-Calculate the LS late start) and LF late finish) values - indicated by w and x - for Task D.

A) w = 2, x = 6
B) w = 4, x = 8
C) w = 5, x = 9
D) w = 6, x = 10
E) None of the above

Question 19

The following software development plan is the basis for the next four questions


-The client has asked for an estimated completion date. What would you tell her?

A) 35 weeks
B) 41 weeks
C) 28 weeks
D) 21 weeks
E) none of the above

Question 20

The table below shows PERT estimates t_e) for activities A through E.
$\text { Time estimates (days) }$
$\begin{array}{|c|c|c|c|c|}\hline \text { Activity }&t(o)&t(m)&t(p)&t(e)\\\hline \mathrm{A} & 4 & 5 & 9 & ? \\\hline \mathrm{B} & 1 & 3 & 7 & ? \\\hline \mathrm{C} & 3 & 6 & 10 & ? \\\hline \mathrm{D} & 2 & 8 & 12 & ? \\\hline \mathrm{E} & 1 & 4 & 6 & ? \\\hline\end{array}$
Based on the table above, the t_e) for activities A, B and C are: .

A) 5 days, 3 days, 6 days
B) 5.500 days, 3.333 days, 6.167 days
C) 6 days, 3.667 days, 6.333 days
D) 3.167 days, 5.333 days, 1.833 days
E) 3 days, 1.667 days, 1.833 days
F) None of the above

Question 21

The following software development plan is the basis for the next four questions


-The client has just asked if it would be possible to have the completed software in 36 weeks. What is the likelihood the project will be completed in that time frame?

A) 54%
B) 90%
C) 100%
D) 33%
E) 63%