MBA First Semester Examination [on-line], 2021
Paper C9 : Production and Operations Management
Full marks—80
The figures in the margin indicate full marks
Answer any five questions
1. a) Give three examples for each of the following and identify two important issues of interest
to an operations manager (Any TWO)
(i)Mass Production system
(ii) Batch Production system
(iii) Job shop
b) There a nine jobs each of which must go through the two machines A and B in the order AB.
Processing times (in hrs.) are given below.
JOB
1
2
3
M/C A
2
5
4
M/C B
6
8
7
Determine a sequence for nine jobs that
idle time of M/C A and M/C B.
4
5
9
6
4
3
will minimize
6
8
9
the total
7
7
3
elapsed
8
9
5
4
8
11
time. Also find out the
[(4+4)+8]
2. a) XYZ Company is evaluating four locations for a new plant and has weighted the relevant
scores as given below. Scores have been assigned with higher values indicative of preferred
conditions. Using these scores develop a qualitative factor comparison for the four locations:
Relevant Factors
Production Cost
Raw material supply
Labour Availability
Cost of Living
Environment
Markets
Total
Assigned Weight
0.35
0.25
0.20
0.05
0.05
0.10
1.00
A
50
70
60
80
50
70
Scores for
Locations
B
C
40 60
80 80
70 60
70 40
60 70
90 80
D
30
60
50
80
90
50
b) Identify the important factors that a location planar may consider with respect to each of the
following:
(I) A multi cuisine restaurant
(II) A state of the art design centre for automobile manufacturing
[8+(4+4)]
3. SS company markets doughnuts through a chain of food stores. It has been experiencing
overproduction and underproduction because forecasting errors. The following data are its demand
in dozens of doughnuts for the past four weeks. Droughnuts are made for the following day, i.e.,
Sunday’s doughnuts production is for Monday’s sales. And so on. The bakery is closed on Sunday, so
Saturday’s production must satisfy demand for both Sunday and Monday.
[16]
Days 4 weeks ago
3 weeks ago
2 weeks ago
last week
Monday
2800 2700
3000
2900
Tuesday
2200 2400
2300
2400
Wednesday
2000 2100
2200
2200
Thursday
2300 2400
2300
2500
Friday
1800 1900
1800
2000
Saturday
190
1800
2100
2000
Sunday (Closed)
Make a forecast for this week based on the following:
o Daily, using a simple four-week moving average
o Daily, using a weighted moving average with weights of 0.40, 0.30, 0.20 and 0.10 (most
recent to the oldest).
o SS is also planning its purchases of ingredients for bread production. If bread demand
had been forecast for last week at 22000 loaves and only 21000 loaves were actually
demanded. What would SS forecast be for this week using exponential smoothing with
α =0.10?
o Suppose with the forecast made in (c) above, this week’s demand actually turn out to be
22500, what would be the new forecast for the next week?
4. (a) Define the differences between MRP I and MRP II.
(b) Product M is made of two units of N and tree units of P. N is made of two units of R an four
units of S. R is made of one unit of S ad three units of T. P is made of two units of t and four units
of U.
(i) Show the bill-of-material (product structure tree)
(ii) If 100 Ms are required, how many units of each component are needed?
(iii) Show both a single-level parts list and an indented parts list.
(c) Consider the following MRP lot-sizing problem; the net requirements are shown for eight scheduling
weeks:
Cost per item: Rs 10; Order or set up cost: Rs 47;
Inventory carrying cost/week: 0.5%
Weekly net requirements:
1
2
3
4
5
6
7
8
50
60
70
60
95
75
60
55
Determine the best lot size using lot-sizing techniques, Lot-for-Lot (L4L), Least Total Cost (LTC) and Least
Unit Cost (LUC).
[2+2+2+2+2+3+3]
5. a) Briefly describe the each of the seven Quality Control (QC) tools.
b) Discuss the concept of Acceptance sampling with the help of operating characteristic
curve. What is significance of AQL and LTPD in acceptance sampling?
[7+ (6+2)]
6. a) An industrial operation consists of five elements with following observed time (OT) and the
performance ratings.
Element
Observed time (min.)
Performance Ratings (%)
A
0.20
85
B
0.08
80
C
0.50
90
D
0.12
85
E
0.10
80
Assuming that rest and personal allowance as 15% and contingency allowance as 2% of the basic
time. Calculate normal time (NT) and standard time (ST) per piece.
b) The annual requirement for a product is 3000 units. The ordering cost is Rs 100 per order and the
cost per unit is Rs 10. The carrying cost per unit per year is 30 percent of unit cost. Find EOQ, If the
ordering cost is reduced to Rs 80, then what would be the further savings in cost for same product.
c) What is Poka Yoke? Can you identify on situation each in your classroom, hostel, and college
administration office that can potentially benefit from the application of this concept? [4+7+5]
7. a) Precision Auto Shafts is a manufacturer of steel shafts and supplies its products to various
automotive companies. It has received a contract from a major auto company for shafts of
diameter 15.0mm  0.30 mm. in order to control the quality of shafts, Precision takes ten
samples of size 3 at regular intervals of 1 hour. The data of diameter measurements obtained is
given in the following table. Prepare a stable mean of sample means (µ) chart and a mean
range(R) chart for the given data.
Sample
No.
Diameter of Shafts (mm)
1
2
3
1
15.0034
15.0167
14.9975
2
14.9925
15.0287
15.0002
3
14.9822
14.9759
15.0427
4
15.2238
15.1756
15.1182
5
14.8896
14.9992
15.2761
6
14.982
14.9775
14.9743
7
15.1002
15.1165
14.9749
8
15.0034
14.9812
14.9672
9
14.9853
14.9993
15.1728
10
15.2549
14.9536
14.9831
[Given constants: A2 = 1.02, D3 = 0 and D4 = 2.57]
b) What is Six Sigma? Mention the contrasts between traditional TQM and Six Sigma.
[10+(2+4)]