Production and Operations Management (sophomore)
Midterm, Spring 2022
Student ID. #
Name:
Instructions
There are 8 questions in the exam, all required. The points for each question are indicated below. All
calculations should clearly indicate the problem data on which an answer is based. Answers without
supporting reasons or calculations will get only partial credits.
Grade Report
Question
Points
1
12
2
12
3
12
4
12
5
12
6
12
7
12
8
16
Total
100
Your Score
Page 1 of 9
1. (12pts) An assembly process of a product consists of 6 steps (i.e., A thru F shown in the figure below)
and 1 worker is assigned to handle each step, for a total of 6 workers. The numbers in parentheses
are the time in minutes for each step of the process.
A (9)
C (16)
E (10)
F (12)
B (10)
D (5)
a) (3pts) What is the cycle time of the process?
b) (3pts) What is the output in terms of product per hour?
c) (3pts) What is the utilization of Step B?
d) (3pts) What is the effect on output of hiring a seventh worker?
assigned?
To which step will this worker be
Page 2 of 9
2. (12pts) Consider the network described in the table below.
Activity
J
K
L
M
N
O
P
Immediate
Predecessor(s)
--J
J
K, M
K, M
L, N
Pessimistic
15
9
10
3
9
10
10
Probable
10
8
6
3
5
7
8
Optimistic
8
7
5
3
1
4
3
a) (3pts) Draw the AON network for the project.
b) (3pts) Fill up the required information of the network in the following table.
Task
Early Start
Early Finish
Late Start
Late Finish
Slack
J
K
L
M
N
O
P
Project
c) (3pts) Calculate the minimum project duration.
d) (3pts) Calculate the critical path.
Page 3 of 9
3. (12pts) The following table represents the data from a manufacturing process of a product. The data
are the quality of the product in weights with ten samples of size four. Construct and plot an x-bar
and R-chart using these data. Is the process in control?
Sample
1
2
3
4
5
6
7
8
9
10
Mean
20.01
19.98
20.25
19.90
20.35
19.23
20.01
19.98
20.56
19.97
Range
0.45
0.67
0.30
0.30
0.36
0.49
0.53
0.40
0.95
0.79
Page 4 of 9
4. (12pts) The quarterly sales for specific educational software over the past four years are given in the
following table.
Quarter 1
Quarter 2
Quarter 3
Quarter 4
YEAR 1
2710
3000
2800
2430
YEAR 2
2800
2850
2840
2250
YEAR 3
2700
3050
3000
2590
YEAR 4
2830
2850
2900
2130
YEAR 5
2750
2950
3050
2230
a) (4pts) Compute the four seasonal factors by using the data of the past five years.
b) (4pts) Forecast the yearly sales for Year 6 using a 3-year moving.
c) (4pts) Forecast the quarterly demand for Year 6 by using the result in part b.
Page 5 of 9
5. (12pts) A company designs a new product layout for a product with the tasks in the layout listed in the
following table. If the company plans to use this production line eight hours a day to produce 400
units per day, answer the following questions.
seconds) for this situation; what is the
Task
Predecessor
Time (seconds)
maximum?
A
50
c) What is the required cycle time (in seconds)
B
A
36
in order to meet the schedule?
C
26
d)
What is the minimum number of workstations
D
22
needed to meet the schedule?
E
B, D
70
e) Balance this line using longest processing
F
C, E
30
time.
a) Draw the network described in the table.
f) What is the efficiency of the balance obtained
b) Without regard to a production schedule,
in part e?
what is the minimum possible cycle time (in
Page 6 of 9
6. (12pts) The relationship of four process strategies (including process focus, repetitive focus, product
focus, and mass customization) to volume and variety is shown in Figure 7.1 of the text. Based on
the criteria of volume and variety, please determine types of layout designs (including Fixed-position
layout, Process-oriented layout, Work-cell layout, and Product-oriented layout) for each of the four
process strategies. Please use practical examples to clarify your explanations.
a) (3pts) for Process Focus
b) (3pts) for Repetitive Focus
c) (3pts) for Product Focus
d) (3pts) for Mass Customization Focus
Page 7 of 9
7. (12pts) Choose one out of the two cases presented before the midterm (with their titles listed below
‘Uber Technologies’, and ‘ALDI: Changing the Landscape of Grocery Shopping’.) The case chosen
by you CANNOT include the one you have presented by yourself. Please describe each of the case
you have chosen based on a) the major contains of the case, and b) what you have learned from the
case.
Chosen Case
Title of the case:
a) (4pts) The major contains of the case: (Your answer shall be limited within five sentences.)
b) (4pts) What have you learned from the case?
(Your answer shall be limited within two sentences.)
c) (4pts) What is the most interesting contain for you?
(Your answer shall be limited within one sentence.)
Page 8 of 9
8. (16pts) Short questions:
a) (4pts) Why Differentiation, Cost, and Response are the three key strategies for product/service
competitive advantage?
b) (4pts) What is ‘Bill of Material (BOM)’?
Give two examples to support your answer.
c) (4pts) How does ‘Location Strategy’ provides competitive advantage for FedEx?
d) (4pts) Explain ‘Productivity’ by using Figure 1.6 of the text.
Page 9 of 9