Operations Management, Student Value Edition & Student Cd For Operations Management
11th Edition
ISBN: 9780133407983
Author: HEIZER, Jay
Publisher: Pearson College Div 2013-03-08
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Textbook Question
Chapter 3, Problem 21P
The estimated times and immediate predecessors for the activities in a project at Howard Umrah’s retinal scanning company are given in the following table. Assume that the activity times are independent.
- a. Calculate the expected time and variance for each activity.
- b. What is the expected completion time of the critical path? What is the expected completion time of the other path in the network?
- c. What is the variance of the critical path? What is the variance of the other path in the network?
- d. If the time to complete path A–C is
normally distributed , what is the probability that this path will be finished in 22 weeks or less? - e. If the time to complete path B–D is normally distributed, what is the probability that this path will be finished in 22 weeks or less?
- f. Explain why the probability that the critical path will be finished in 22 weeks or less is not necessarily the probability that the project will be finished in 22 weeks or less.
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The estimated times and immediate predecessors for the activities in a project a t George Kyparis's retinal scanning company are given in the following table. Assume that the activitytimes are independent. a) Calculate the expected time and variance for each activity.b) What is the expected completion time of the critical path?What is the expected completion time of the other path in the network?c) What is the variance of the critical path? Wha t is the variance of the other path in the network?d) If the time to complete path A-C is normally distributed, what is the probability that this path will be fini shed in 22 weeks or less?e) If the time to complete path B- D is normally distributed, what is the probability that this path will be finished in 22 weeks or less?f) Explain why the probability that the critical path will be finished in 22 weeks or…
The estimated times and immediate predecessorsfor the activities in a project at George Kyparis’s retinal scan-ning company are given in the following table. Assume thatthe activity times are independent.
a) Calculate the expected time and variance for each activity.b) What is the expected completion time of the critical path?What is the expected completion time of the other path inthe network?c) What is the variance of the critical path? What is the vari-ance of the other path in the network?d) If the time to complete path A–C is normally distributed,what is the probability that this path will be finished in22 weeks or less?e) If the time to complete path B–D is normally distributed,what is the probability that this path will be finished in22 weeks or less?f) Explain why the probability that the critical path will befinished in 22 weeks or less is not necessarily the probabil-ity that the project will be finished in 22 weeks or less.
Consider a project that has been modeled as in the table below:
a. Draw the PERT/CPM network for this project and determine the project’sexpected completion time μP and its critical path.
b. Suppose the standard deviations of the activity durations are σA = 2,σB = 1, σC = 0, σD = 2, σE = 3, and σF = 0. Then please estimate the standarddeviation of the overall project’s standard deviation σP .
c. Suppose for the standard Normal random variable Z, we know P[−1 ≤Z ≤ +1] ' 68%, P[−2 ≤ Z ≤ +2] ' 95%, and P[−3 ≤ Z ≤ +3] ' 99.7%. Then,approximately what time T is one for which there is only a less than 2.5% chance forthe completion time to beat (be shorter than)?
*Please solve a-c and neatly write or type your answers, showing your steps, NO EXCEL*
Chapter 3 Solutions
Operations Management, Student Value Edition & Student Cd For Operations Management
Ch. 3 - Give an example of a situation in which project...Ch. 3 - Explain the purpose of project organization.Ch. 3 - What are the three phases involved in the...Ch. 3 - What are some of the questions that can be...Ch. 3 - Define work breakdown structure. How is it used?Ch. 3 - What is the use of Gantt charts in project...Ch. 3 - What is the difference between an...Ch. 3 - What is the significance of the critical path?Ch. 3 - What would a project manager have to do to crash...Ch. 3 - Describe how expected activity times and variances...
Ch. 3 - Define earliest start, earliest Finish, latest...Ch. 3 - Students are sometimes confused by the concept of...Ch. 3 - What are dummy activities? Why are they used in...Ch. 3 - What are the three time estimates used with PERT?Ch. 3 - Would a project manager ever consider crashing a...Ch. 3 - How is the variance of the total project computed...Ch. 3 - Describe the meaning of slack, and discuss how it...Ch. 3 - How can we determine the probability that a...Ch. 3 - Name some of the widely used project management...Ch. 3 - The work breakdown structure (WBS) for building a...Ch. 3 - 3.2 Robert Day has decided to run for a seat as...Ch. 3 - Draw the activity-on-node (AON) project network...Ch. 3 - Given the activities whose sequence is described...Ch. 3 - 3.5 Using AOA, diagram the network described below...Ch. 3 - Stephen Hall is developing a program in supply...Ch. 3 - Task time estimates for the modification of an...Ch. 3 - 3.8 The City Commission of Nashville has decided...Ch. 3 - Refer to the table in Problem 3.8. a. Draw the AON...Ch. 3 - The activities needed to build a prototype laser...Ch. 3 - Dave Fletcher (see Problem 3.10) was able to...Ch. 3 - The activities described by the following table...Ch. 3 - A renovation of the gift shop at Orlando Amway...Ch. 3 - Kelle Carpet and Trim installs carpet in...Ch. 3 - The following is a table of activities associated...Ch. 3 - Assume that the activities in Problem 3.15 have...Ch. 3 - Bill Fennema, president of Fennema Hospitality,...Ch. 3 - What is the minimum cost of crashing the following...Ch. 3 - Three activities are candidates for crashing on a...Ch. 3 - Development of Version 2.0 of a particular...Ch. 3 - The estimated times and immediate predecessors for...Ch. 3 - Rich Cole Control Devices, Inc., produces...Ch. 3 - Four Squares Productions, a firm hired to...Ch. 3 - Using PERT, Adam Munson was able to determine that...Ch. 3 - Clark Products makes pizza ovens for commercial...Ch. 3 - The Tesla 6 is a new custom-designed sports car....Ch. 3 - TABLE 3.6 Southwestern University Project 1....Ch. 3 - TABLE 3.6 Southwestern University Project 2 What...Ch. 3 - TABLE 3.6 Southwestern University Project 3. If it...Ch. 3 - Project Management at Arnold Palmer Hospital Video...Ch. 3 - The equivalent of a new kindergarten class is born...Ch. 3 - The equivalent of a new kindergarten class is born...Ch. 3 - The equivalent of a new kindergarten class is born...Ch. 3 - At the Hard Rock Cafe, like many organizations,...Ch. 3 - At the Hard Rock Cafe, like many organizations,...Ch. 3 - At the Hard Rock Cafe, like many organizations,...Ch. 3 - At the Hard Rock Cafe, like many organizations,...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, operations-management and related others by exploring similar questions and additional content below.Similar questions
- A plumber has decided to use the techniques of project management in order to plan a job. He knew all the different activities of the job, their precedence and their average durations. They are shown on the table below.ActivityDuration (days)Preceding activitiesA3NoneB3NoneC4AD9AE4B and CRequired:1. Draw a network diagram representing the sequence of activities and the dependence between them.2. Determine how long it will take to complete the job by conducting the forward pass3. By conducting the backward pass, identify the critical path and the non-critical path(s).Note:The work for this task should be produced using Word drawing facilities. The forward and backward passes should be clearly shown on the diagram. The calculations should be shown next to the network diagram.arrow_forwardThe estimated times and immediate predecessors for the activities in a project at Howard Umrah's retinal scanning company are given in the following table. Assume that the activity times are independent. Time (weeks) Immediate Time (weeks) Immediate Activity a m b Predecessor(s) Activity a m b Predecessor(s) A 8 10 13 — C 9 10 13 A B 4 10 16 — D 6 8 12 B This exercise contains only parts a, b, c, and d. a) Based on the activity time estimates, the expected times and variance for each of the activities are (round your response to two decimal places): Activity Expected Time Variance A _________ ___________ B ______________ __________…arrow_forwardUse the Program Evaluation and Review Technique to represent the project in an activity network. In conjunction with the Critical Path Method, use the activity network to find the shortest time possible to complete the project, to identify the critical jobs in the project, and to determine the earliest and latest that each activity can start and finish without making the project completion longer.a=1, b=1, c=6, d=5, e=2, f=5; andab=1x1=1, bc=1x6=6, cd=6x5=30, de=5x2=10, ef=2x5=10, af=1x5=5.arrow_forward
- Consider a project that has been modeled as in the table below. Part a) Draw the PERT/CPM network for this project and determine the project’s expected completion time μP and its critical path. Part b) Suppose the standard deviations of the activity durations are σA = 2, σB = 1, σC = 0, σD = 2, σE = 3, and σF = 0. Then please estimate the standard deviation of the overall project’s standard deviation σP . Part c) Suppose for the standard Normal random variable Z, we know P[−1 ≤ Z ≤ +1] ' 68%, P[−2 ≤ Z ≤ +2] ' 95%, and P[−3 ≤ Z ≤ +3] ' 99.7%. Then, approximately what time T is one for which there is only a less than 2.5% chance for the completion time to beat (be shorter than)? *Please answer a-c and type your work and answers or write them neatly please* Thank youarrow_forward1. The estimated times and immediate predecessors for the activities in a project at Howard Umrah's retinal scanning company are given in the following table. Assume that the activity times are independent. Time (weeks) Immediate Time (weeks) Immediate Activity a m b Predecessor(s) Activity a m b Predecessor(s) A 9 10 13 — C 8 9 12 A B 5 11 16 — D 4 10 12 B This exercise contains only parts a, b, c, and d. a) Based on the activity time estimates, the expected times and variance for each of the activities are (round your response to two decimal places): Activity Expected Time Variance A _____ _______ B ______ ________ C ______ ________ D…arrow_forwardA project manager has compiled a list of major activities that will be required to install a computer information system in her firm. The list includes estimated completion times for activitiesand precedence relationships.ActivityImmediatePredecessorEstimatedTimes (weeks)A — 2-4-6D A 6-8-10E D 7-9-12H E 2-3-5F A 3-4-8G F 5-7-9ActivityImmediatePredecessorEstimatedTimes (weeks)B — 2-2-3I B 2-3-6J I 3-4-5K J 4-5-8C — 5-8-12M C 1-1-1N M 6-7-11O N 8-9-13End H, G, K, Oa. Construct a network diagram. You can use either AOA or AON (see Example 5).b. If the project is finished within 26 weeks of its start, the project manager will receive a bonusof $1,000; and if the project is finished within 27 weeks of its start, the bonus will be $500.Find the probability of each bonus.arrow_forward
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