Geethanjali: Department of Mechanical Engineering
Geethanjali: Department of Mechanical Engineering
Geethanjali: Department of Mechanical Engineering
Geethanjali
College of Engineering and Technology (Autonomous)
Cheeryal (V), Keesara (M), Medchal Dist 501301. Telangana State
(Affiliated to JNTUH, Approved by AICTE, New Delhi, Accredited by NAAC ‘A’ Grade, Accredited by NBA)
COURSE HAND-OUT
OPERATIONS RESEARCH
IV Year B.Tech I Semester
June 2019 – November 2020
To bring out creativity in students that would promote innovation, research and
entrepreneurship.
PO2: Problem analysis: Identify, formulate, review research literature, and analyze
complex engineering problems reaching substantiated conclusions using first
principles of mathematics, natural sciences, and engineering sciences.
PO5: Modern tool usage: Create, select, and apply appropriate techniques,
resources, and modern engineering and IT tools including prediction and
Course Handout: IV Year I Sem Page 3
Department of Mechanical Engineering
PO6: The engineer and society: Apply reasoning informed by the contextual
knowledge to assess societal, health, safety, legal and cultural issues and the
consequent responsibilities relevant to the professional engineering practice.
PO8: Ethics: Apply ethical principles and commit to professional ethics and
responsibilities and norms of the engineering practice.
PO12: Life-long learning: Recognize the need for, and have the preparation and
ability to engage in independent and life-long learning in the broadest context
of technological change.
PSO2: Able to analyze, design and develop/model mechanical and its allied
systems using software tools such as AUTOCAD, ANSYS, Creo etc
PSO3: Able to design layouts for process and manufacturing industry taking into
consideration optimization of resources for effective operation and
maintenance.
INDEX Page No
1 Semester Plan
2 Assignment Schedule
3 Scheme
4 ME411: Operations Research
3. SCHEME
FOURTH YEAR – SEMESTER – I
Scheme of
Category
No. of Periods Examination with No. of
S. Course per Week Credits
Course Maximum Marks
No Code
L T P/D CIE SEE Tot C
1 16ME4101 Heat Transfer PC 3 1 - 30 70 100 3
2 16ME4102 Operations Research PC 3 1 - 30 70 100 3
Soft Core – II
Industrial Engineering
16ME4103
3 and Management SC 3 1 - 30 70 100 3
Production Planning
16ME4104
and Control
Professional Elective – III
Non-destructive
16ME4105
Testing
4 16ME4106 Robotic Engineering PE 3 - - 30 70 100 3
Work Study and
16ME4107
Ergonomics
16ME4108 Mechatronics
Open Elective - II
Supply Chain
16MB4131
Management
Knowledge
16CS4132
Management
5 Energy Conservation OE 3 - - 30 70 100 3
16EE4133
and Management
Basics of
16EC4134 Communication
Systems (ECE)
16CE4136 Building Technology
Open Elective – III
16MB4141 Banking and Insurance
16CS4142 Database Systems
Micro-Electro-
16EE4143
Mechanical Systems
Principles of Wireless
16EC4144 Communication
6 Systems (ECE) OE 3 - - 30 70 100 3
16CE4146 Green Buildings
Foreign Language-
16EN4147
French
Foreign Language-
16EN4148
Spanish
Foreign Language-
16EN4149
German
7 Soft Core - II Lab. SC - - 3 30 70 100 2
Course Handout: IV Year I Sem Page 7
Department of Mechanical Engineering
Engineers, scientists, analysts and managers are often faced with the challenge of making
tradeoffs between different factors in order to achieve desirable outcomes. Optimization is
the process of choosing these trade-offs in the best way. Optimization problems, having
reached a degree of maturity over the past several years, are encountered in physical sciences,
engineering, economics, industry, planning, and many other areas of human activity.
Objective of the course is to familiarize the students with standard methods of solving
optimization problems.
Operation Research is also called OR for short and it is a scientific approach to decision
making which seeks to determine how best to design and operate a system under conditions
requiring allocation of scarce resources. Operations research as a field, primarily has a set or
collection of algorithms which act as tools for problems solving in chosen application areas.
OR has extensive applications in engineering, business and public systems and is also used
by manufacturing and service industries to solve their day to day problems.
This course deals with details of various aspects associated with optimization These include
description of optimization techniques, namely, Linear Programming, and their applications
to various engineering and science disciplines including economics and finance. Multi-
objective optimization which handles optimization aspects of more than one objective is also
discussed.
SYLLABUS
COURSE OBJECTIVES:
1. Students will understand the significance of Operations Research concept and techniques
and formulation of LPP models.
2. Students will understand the Algorithms of Graphical and Simplex Methods.
3. Students will understand the Transportation and Assignment techniques.
4. Students will understand the concepts of sequencing and Replacement.
5. Students will understand the concepts of Game theory and Inventory Control.
6. Students will understand the concepts of queuing theory and DPP.
COURSE OUTCOMES:
At the end of the course, student would be able to
Bloom’s
CO No STATEMENT Taxonomy
Level
Identify the importance and value of Operations Research and Applying,
mathematical formulation in solving practical problems in industry Creating
CO1
and Formulate a managerial decision problem into a mathematical (Level 3 & 6)
model
Applying,
Formulate and solve engineering and managerial situations as
CO2 Creating
Transportation and Assignment problems.
(Level 3 & 6)
Applying,
CO3 Apply sequencing and replacement concepts in industry applications
(Level 3)
Applying,
CO4 Apply game theory and inventory concepts in industry applications
(Level 3)
Formulate multi-stage applications into a dynamic programming Applying,
CO5 framework and Apply queuing theory concepts in industry Creating
applications (Level 3 & 6)
Detailed Syllabus:
UNIT-I: DEVELOPMENT: Definition– Characteristics and Phases – Types of models –
Operations Research models – applications.
ALLOCATION: Linear Programming Problem - Formulation – Graphical solution –
Simplex method – Artificial variables techniques: Two–phase method, Big-M method;
Duality Principle.
UNIT-II: TRANSPORTATION PROBLEM: Formulation – Optimal solution, unbalanced
transportation problem – Degeneracy.
ASSIGNMENT PROBLEM: Formulation – Optimal solution - Variants of Assignment
Problem; Traveling Salesman problem.
UNIT-III: JOB SEQUENCING: Introduction – Flow Shop sequencing, n jobs through 2
machines, n jobs through 3 machines, Job shop sequencing, 2 jobs through ‘m’ machines -
graphical model.
REPLACEMENT MODEL: Introduction – Replacement of items that deteriorate with
time, when money value is not counted and counted, Replacement of items that fail
completely, Group Replacement.
UNIT-IV: THEORY OF GAMES: Introduction –Terminology – Solution of games with
saddle points and without saddle points, 2 x 2 games, m x 2 and 2 x n games - graphical
method, m x n games, dominance principle.
INVENTORY MODELS: Introduction – Concept of EOQ, Single item - Deterministic
models – Types - Purchase inventory models with one price break and multiple price breaks,
Stochastic models – demand discrete variable or continuous variable – Single Period model
with no setup cost.
UNIT-V: QUEUING THEORY: Introduction – Terminology - Single Channel – Poisson
arrivals and Exponential Service times – with infinite population and finite population
models– Multichannel – Poisson arrivals and exponential service times with infinite
population.
DYNAMIC PROGRAMMING: Introduction – Terminology - Bellman’s Principle of
Optimality – Applications of dynamic programming - shortest path problem – linear
programming problem.
References:
Text books:
1. J.K.Sharma, Operation Research, MacMilan India Ltd, 5th edition, 2012.
2. A.C.S.Kumar, Operations Research, Yesdee, 2015.
Reference books:
1. A.M.Natarajan, P.Balasubramaniam, A. Tamilarasi, Operations Research, Pearson
Education,2009
2. Harvey M.Wagner, Principles of Operations Research, Prentice Hall, 1975.
3. Frederick S. Hillier &Gerald J.Libermann, Introduction to Operation Research, TMH,
2001.
4. Hamdy A.Taha, Introduction to Operation Research, Prentice Hall, 1997.
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12 PSO1 PSO2 PSO3
CO1 3 2 - - 3 - - - - - - 2 - - -
CO2 3 2 2 - 3 - - - - - - 2 - - -
CO3 3 2 2 - 3 - - - - - - 2 - - -
CO4 3 2 2 - 3 - - - - - - 2 - - -
CO5 3 2 2 - 3 - - - - - - 2 - - -
C401 3.00 2.00 2.00 - 3.00 - - - - - - 2.00 - - -
1- Low correlation (Low), 2- Medium correlation (Medium), 3-High correlation (High)
Students will be able to analyze the different codes used in part programming so that they
CO2 - PO5 H
can develop effective methods
CO2 - PO12 M Ability to understand and adopt the new innovative methods in transportation and assignment
Students will be able to apply and solve different operations research methods such as job
CO3 - PO1 H
sequencing and replacement
Students will be able to analyze and solve different operations research methods such as job
CO3 - PO2 M sequencing and replacement models in different mechanical streams such as thermal,
manufacturing etc.,
Students will be able to formulate, design and solve different operations research methods
CO3 - PO3 M
such as job sequencing and replacement models for societal benefit.
Students will be able to use modern tools and solve different operations research methods
CO3 - PO5 H
such as job sequencing and replacement models.
Ability to understand and adopt the new innovative methods in such as job sequencing and
CO3 - PO12 M
replacement models
Students will be able to understand the importance of different operations research methods
CO4 - PO1 H
such as theory of games and inventory.
Students will be able to analyze and solve different operations research methods such as
CO4 - PO2 M theory of game and inventory models in different mechanical streams such as thermal,
manufacturing etc.,
Students will be able to formulate, design and solve different operations research methods
CO4 - PO3 M
such as theory of games and inventory models for societal benefit.
Students will be able to use modern tools and solve different operations research methods
CO4 - PO5 H
such as theory of games and inventory models.
Ability to understand and adopt the new innovative methods in such as theory of games and
CO4 - PO12 M
inventory models
CO5 - PO1 H Students will be able to apply and solve different operations research methods such as
RELEVANCE PROPOSED
S.No DESCRIPTION
TO PO/PSO ACTIONS
Delivery/Instructional Methodologies:
Tutorials Others
Other
EVALUATION SCHEME
Mid Examinations 25
Assignments 5
Total 30
Part- –A
20
Objective type questions
Part –B
There should be five questions from five units. Each question should be for maximum
of 10 Marks
50
Each unit will have an internal choice.
Both the questions should be of the same complexity in terms of COs and Bloom’s
taxonomy level.
Total 70
CIE 40%
Direct
Questionnaire
Students -
Based on COs
Once before I- Mid and once
Online feedback 15%
before II -mid
S. Lecture Reference to
UNIT Learning Objectives Topics to be Covered
No. Nos Text book
To understand the meaning of operations
Evolution and development of operations
1 I research and its evolution and 1 T1 and T2
research
development
To Explain characteristics, OR phases and
its applications in different area such as Characteristics and Phases, Operation Research
2 I 2-3 T1 and T2
finance, physical sciences, engineering, Models and its Applications
economics, industry, planning etc.
3 I To understand the Formulation of LPP Formulation of LPP and some Problems 4-6 T1 and T2
Discussion on how to solve two variables
4 I LP models by the graphical solution Graphical Solutions and some Problems 7-8 T1 and T2
procedure
To obtain an understanding of why and
how the simplex calculations are made
5 I Simplex Method, 9 - 10 T1 and T2
and know how to recognize the special
situations
To solve the problems using special Artificial Variable Technique- Big M Method
6 I 11 - 13 T1 and T2
solution algorithms and Two Phase Method and some Problems
Introduction to Transportation Problems, Finding
Initial Basic Feasible Solution (IBFS) by using
To formulate transportation as LPP and different methods namely, NWCM, LCEM,
7 II 14 - 20 T1 and T2
how to solve these problems RMM CMM, VAM, Optimality Test,
Variations in TP Unbalanced TP and some
Problems
amount required per acre is 100 kgs each for tomatoes and lettuce, and 50 kgs for
radishes. Labour required for sowing and harvesting per acre is 5 man-days for tomatoes
and radishes, and 6 man-days for lettuce. A total of 400 man-days of labour are available
at Rs 20.00 per man-day. Formulate this as a Linear-Programming model to maximize
the farmers total profit.
19. Solve the following LPP using graphical method.
Maximize, Z = 10X1 + 8X2
Subject to constraints
X1 + 2X2 ≤ 1000
X1 ≤ 300
X2 ≤ 500
X1 and X2 ≥ 0
20. Use the graphical method to solve the following LP Problem
Minimize = 20x1 + 10x2
Subject To
x1 +2x2 40
3x1+x2 30
4x1+3x2 60
x1, x2, 0
21. Use the graphical method to solve the problem:
Maximize Z = 2x1 +x2,
Subject to
x2 ≤ 10
2x1 + 5x2 ≤ 60
x1 + x2 ≤ 18
3x1 + x2 ≤ 44
and x1 ≥ 0, x2 ≥ 0
22. Solve graphically:
Maximize z = 3x1 5x2
Subjected to constraints
2 x1 6x2 50
3 x1 2x2 35
5x1 3x2 10
3 x2 20 where x1 , x2 , x3 0
23. Solve the following LPP using graphical method and verify by simplex method
Subjected to constraints
x1 2 x2 5x3 90
2 x1 x 2 x3 60
3x1 x2 2 x3 80 where x1 , x2 , x3 0
Subject to constraints
3x1 +10x2 + 5x3 15
33x1-10x2 +9x3 33
x1+2x2+3x3 4
x1, x2, x3 0
UNIT –II: Transportation problems and Assignment Problems
1. What is meant by optimal solution
2. Explain the steps in transportation algorithm.
3. When does degeneracy occur in Transportation Problem?
1. Distinguish between assignment and allocation problem. Write the situation where an
assignment problem can arise?
4. Give the mathematical formulation of transportation problem.
5. What is meant by balanced transportation problem? Give the method of solving
transportation problem with capacities.
6. With the example of your choice, explain the algorithm of North West corner method to
obtain IBFS in a transportation problem.
7. What is IBFS. Give step by step approach to find IBFS in a transportation problem using
Vogel’s Approximation method.
8. Write the algorithm to find IBFS in a transportation problem using least cost entry
method. Give suitable examples.
9. What is assignment problem?
10. How the assignment problem can be viewed as a linear programming problem?
11. Formulate the travelling –Salesman problem as an assignment problem.
12. What is unbalanced assignment problem? How is it solved by the Hungarian method?
13. What is the difference between transportation problem and assignment problem?
14. Explain the Hungarian method to solve an assignment problem.
15. What is the unbalanced Assignment problem? How is it solved by the Hungarian method?
16. How can you maximize an objective function in the Assignment problem?
17. Find the total cost using North-west corner method. Also find the optimal assignment.
W1 W2 W3 W4 Capacity
F1 95 105 80 15 12
F2 115 180 40 30 7
F3 195 180 95 70 5
Requirement 5 4 4 11
18. Solve the following transportation problem, by findings; find the IBFS by North West
corner rule and OBFS by stepping stone method, where the entries are cost coefficients.
To Destination Availability
1 2 3 4
From 1 15 0 20 10 50
Origins 2 12 8 11 20 50
3 0 16 14 18 100
Requirement 30 40 60 70 200
19. Solve the following transportation problem for the optimal solutions. Use North-West
corner method to generate initial BFS.
Factory\Warehouse W X Y Z Availability
A 19 30 50 10 7
B 70 30 40 60 9
C 40 8 70 20 18
Requirement 5 8 7 14
20. A company has three plants A, B, C which supplies to ware houses 1, 2, 3, 4, 5. Monthly
plant capacities are 800, 800, 900 units respectively while the monthly requirements at
the warehouses are 400, 400, 500, 400, 800 units respectively. The unit transportation
costs are shown in table below. Determine optimum distribution for the company in order
to minimize the total transportation cost.
1 2 3 4 5
A 5 8 6 6 3
Plants
B 4 7 7 6 6
C 8 4 6 6 3
21. Use Vogel’s’ approximate method to obtain an initial basic feasible solution of the
transportation problem and find optimal solution
Warehouse
W X Y Z Supply
Factory
A 11 13 17 14 250
B 16 18 14 10 300
C 21 24 13 10 400
Demand 200 225 275 250
22. An oil corporation has got three refineries P, Q and R and it has to send petrol to four
different depots A, B, C and D. The cost of shipping 1 gallon of petrol and the available
petrol at the refineries are given in the table. The requirement of the depots and the
available petrol at the refineries are also given. Find the minimum cost of shipping after
obtaining an initial solution by VAM.
Depots
Available
A B C D
P 10 12 15 8 130
Refineries
Q 11 11 9 10 150
R 20 9 7 18 170
Required 90 100 140 120
23. Find the initial basic feasible solution for the following transportation problem by VAM
method and test the solution for optimality by MODI method.
A B C D E Supply
F 2 1 4 2 5 50
G 4 3 6 4 5 60
H 1 7 7 5 8 75
I 8 8 7 6 9 80
Demand 75 60 50 80 100
24. There are three sources or origins which store a given product. These sources supply
these products to four dealers. The capacities of the sources (S1) and the demands at
dealers (D1) are as given below
S1 = 150, S2 = 40, S3 = 80, D1 = 90, D2 = 70, D3 = 50, D4 = 60
The cost of transporting the product from various sources to various dealers is shown
in the table below
D1 D2 D3 D4
S1 27 23 31 69
S2 10 45 40 32
S3 30 54 35 57
Find out the optimal solution for transporting the products at a minimum cost.
25. Determine the initial basic feasible solution to the following transportation problem
using northwest corner cell method.
Destination Supply
10 22 0 22 8
Origin
15 20 12 8 13
20 12 10 15 11
Demand 5 11 8 8
27. Find the initial basic feasible solution for the following transportation problem by VAM
method and test the solution for optimality by MODI method.
A B C D Supply
F 5 2 4 3 22
G 4 8 1 6 15
H 4 6 7 5 8
Demand 7 12 17 9
28. Raju and Co. has four lathe machines on which four workers operate. Any worker can
operate any machine but due to the difference in skill and machine complexity the time
of operation varies. The average times in hours when same job dome on each machine by
each worker is given below.
L1 L2 L3 L4
W1 7 6 4 9
W2 5 5 8 8
W3 4 5 4 6
W4 7 8 5 8
29. Find the optimal solution for the assignment problem with the following cost matrix.
I II III IV V
A 11 17 8 16 20
B 9 7 12 6 15
C 13 16 15 12 16
D 21 24 17 28 26
E 14 10 12 11 15
30. Suggest optimum assignment of 4 workers A, B, C and D to 4 jobs, I, II, III and IV. The
time taken by different workers in completing the different jobs is given in table below.
Jobs
I II III IV
A 5 5 - 2
Workers
B 7 4 2 3
C 9 3 5 -
D 7 2 6 7
31. A hospital wants to purchase three different types of medical equipments and five
manufacturers have come forward to supply one or all the three machines. However, the
hospital’s policy is not to accept more than one machine from any one of the
manufactures. The data relating to the price (in thousands of rupees) quoted by the
different manufactures are as given in table. Find the optimum assignment policy.
Machines
1 2 3
A 30 31 27
Sub
B 28 29 26
Ordinates
C 29 30 28
D 28 31 27
E 31 29 26
32. Find the optimal solution for the assignment problem with the following cost Matrix
I II III IV
A 12 30 21 15
B 18 32 09 31
C 44 25 24 21
D 23 30 28 14
33. Find the optimal solution for the assignment problem with the following cost Matrix
I II III IV
A 5 40 20 5
B 25 35 30 25
C 15 25 20 10
D 15 5 30 15
Job 1 2 3 4 5 6
Machine A 12 10 9 14 7 9
Machine B 7 6 6 5 4 4
Machine C 6 5 6 4 2 4
Order of the processing of each job is ACB. Sequence suggested is 5-3-6-2-1-4. Find the total
time elapsed for the sequence suggested.
18. Consider following 3 machines (A, B, C) and 7 jobs problem. Find the optimal sequence
if the processing order is ABC and also determine makes pan time for the optimal
sequence.
Job 1 2 3 4 5 6 7
A 5 7 3 4 6 7 12
B 2 6 7 5 9 5 8
C 10 12 11 13 12 10 11
19. We have five jobs each of which must go through the machine A, B and C in the order
ABC:
Processing Times (in Hours)
Job No 1 2 3 4 5
Machine A 5 7 6 9 5
Machine B 2 1 4 5 3
Machine C 3 7 5 6 7
Determine a sequence for the jobs that will minimize the total elapsed time
20. The maintenance cost and resale value per year of a machine whose purchase price is Rs.
7000 is given below
Year 1 2 3 4 5 6 7 8
Maintenance cost in Rs 900 1200 1600 2100 2800 3700 4700 5900
Resale value in Rs 4000 2000 1200 600 500 400 400 400
When the machine should be replaced.
21. An individual is planning to purchase a car will cost Rs. 1, 20, 000. The resale value of
the car at the end of the year is 85% of the previous year value. Maintenance and
operation costs during the first year are Rs. 20, 000 and they increase by 15% every year.
The minimum resale value of car can be Rs. 40, 000. (a) When should the car be replaced
to minimize average annual cost (ignore initial) (b) If interest of 12% is assumed, when
should the car be replaced?
22. A truck owner finds from his pas records that the maintenance cost per year of a truck
whose purchase price is Rs. 8000, are given below:
Year 1 2 3 4 5 6 7 8
Maintenance cost in Rs. 1000 1300 1700 2200 2900 3800 4800 6000
Resale Price 4000 2000 1200 600 500 400 400 400
Determine at what time it is profitable to replace the truck?
23. A machine owner finds from his past records that the costs per year of maintaining a
machine whose purchase price is Rs.6000 are as given below:
Year 1 2 3 4 5 6 7 8
Maintenance
1000 1200 1400 1800 2300 2800 3400 4000
cost (Rs)
Resale Price 3000 1500 750 375 200 200 200 200
24. Equipment A costs Rs.9000. Annual operating costs are Rs.200 for the first year and then
increases by Rs.2,000 every year. Determine the best age at which to replace the
equipment. Equipment B costs Rs.10, 000.Annual operating costs are Rs.400 for the first
year and then increases by Rs.800 every year. Now you have a equipment of type A
which is one year old. Should you replace it with B, if so when?
25. A scooter cost Rs 6,000 when new. The running cost and salvage value at the end of
different years are as follows: (in Rs):
Year 1 2 3 4 5 6 7
Running cost 1200 1400 1600 1800 2000 2000 2400
Scrap Values 4000 2666 2000 1500 1000 600 600
26. A truck is priced for Rs.60000 and running costs are at Rs.6000 for each of first 4 years
increasing by Rs.2000 per year in the fifth and subsequent years. If money is worth 10%,
when the truck should be replaced. Assume scrap value = 0.
27. The yearly cost of two machines A and B, when money value is neglected is shown
below. Find their cost patterns if money is worth 10 per cent per year and hence find
which machine is more economical.
Year: 1 2 3
Machine A (Rs): 1,800 1,200 1,400
Machine B (Rs): 2,800 1,200 1,400
28. A manufacturer is overfed two machines A and B. A is priced at Rs.5000 and running
costs are estimated at Rs.800 for each of the first five years, creasing by Rs.200per year
in the sixth and subsequent years. Machine B, which has the same capacity as A, costs
Rs.2500 but will have running costs of Rs.1200 per year for six years, increasing by
Rs.2000 per year thereafter. If the money is worth 10% per year, which machine should
be purchased assuming that both machines will eventually be sold for a scrap at a
negligible value?
29. If the interest rate is 10 per cent per year and running costs are assumed to have occurred
mid year, find when the scooter should be replaced. The following failure rates have
been observed for a certain type of light bulb.
End of Week: 1 2 3 4 5 6 7 8
Probability of failure: 0.05 0.13 0.25 0.43 0.68 0.88 0.96 1.00
The cost of replacing an individual bulb is Rs. 2.25. The decision is made to replace all
bulbs simultaneously at fixed intervals, and also to replace individual bulbs as they fail in
service. If the cost of group replacement is 60 paise per bulb and the total number of
bulbs is 1,000, what is the best interval between group replacements?
30. A newspaper boy buys papers for 50 paise each and sells them for 90 paise each. He
cannot return unsold newspapers. Daily demand R for news papers follows the
distribution.
R 10 11 12 13 14 15 16
probability 0.05 0.16 0.42 0.18 0.10 0.05 0.05
If each day’s demand is independent of the previous day’s, how many papers should be
ordered each day?
31. A computer contains 10000 resistors. When any resistor fails, it is replaced. The cost of
replacing a resistor individually is Rs 1 only. If all the resistors are replaced at the same
time, cost per resistor would be reduced to 35 paisa. The % of surviving resistors say S(t)
at the end of month t and the P(t) the probability of failure during the month t are
t 0 1 2 3 4 5 6
S(t) 100 97 90 70 30 15 0
P(t) -- 0.03 0.07 0.2 0.4 0.15 0.15
What is the optimum replacement policy?
32. A factory has large number of bulbs, all of which must be in working condition. The
mortality of Bulbs is given in the following table:
Week : 1 2 3 4 5 6
Proportion of bulbs failing : 0.10 0.15 0.25 0.35 0.12 0.03
If a bulb fails in service, it costs Rs 3.50 to be replaced; but if all the bulbs are replaced at
a time it costs Rs 1.20 each, nd the optimum group replacement policy
Player B
B1 B2 B3
A1 1 3 11
Player A
A2 8 5 2
25. Write the assumptions made in game theory. Solve the following game graphically
1 -3
3 5
-1 6
4 1
2 2
-5 0
27. Solve the game given in the table by reducing to 2 X 2 game by graphical method.
PLAYER B
I II III
PLAYER A I 4 -1 0
II -1 4 -2
28. A stockiest has to supply 400 units of a product every Monday to his customers. He gets
the product at Rs.50 per unit from the manufacturer. The cost of ordering and
transportation from the manufacturer is Rs.75 per order. The cost of carrying inventory is
7.5% per year of the cost of the product. Find (a) the economic lot size (b) the total
optimal cost.
29. A company uses 24000 units of a raw material which costs Rs. 12.50 per unit. Placing
each order costs Rs 22.50 and the carrying cost is 5.4% per year of the average
inventory. Find the economic order quantity and the total inventory cost ( including the
cost of the material)
30. Find the most economic batch quantity of a product on a machine if the production rate
of the item on the machine is 300 pieces/day and the demand is uniform at the rate of
150 pieces/day. The set-up cost is Rs.300 per batch and the cost of holding one item in
inventory is Rs.0.81 per day. How will the batch quantity vary if the machine production
rate was infinite?
31. Find the most economic batch quantity of a product on a machine of the production rate
of the item on the machine is 300 pieces/day and the demand is uniform at the rate of 150
pieces/day. The set-up cost is Rs.300 per batch and the cost of holding one item in
IV Year B.Tech I Semester, Course Handout Page 33
Department of Mechanical Engineering
inventory is Rs.0.81 per day. How will the batch quantity vary if the machine production
rate was infinite?
32. The annual demand for an items is 3200 units, the unit cost is Rs. 6/- and inventory
charges 25% per annum. If the cost of one procurement is Rs. 150/-, Determine (i).
Economic Order Quantity (ii). Number of orders per year (iii). Time between two
consecutive orders (iv). The optimal cost.
33. The demand for an item in a company is 15000 units per year and the company can
produce the items at a rate of 300 per month. The cost of one set-up is Rs. 500 and
holding cost of 1 unit per month is 15 paise. The shortage cost of one unit is Rs. 20 per
month. Determine: (a) Optimum production batch quantity and number of shortages (b)
Optimum cycle time and production time. (c) Maximum inventory level in the cycle. (d)
Total associated cost per year if the cost of the items is Rs. 20 per unit.
34. A company requires 10000 units of an item per annum. The cost of ordering is Rs 100 per
order. The inventory carrying cost is 20%.The unit price of the item is Rs 10.Calculate (a)
Economic order quantity (b) Optimum total annual cost
35. In a two wheeler manufacturing company pistons are being fed into the main assembly
line from a product line situated in the next bay. The annual demand for the pistons is
8000 units and the annual production capacity of the product line manufacturing the
pistons is 12000 units. The set up cost is Rs.125 per setup and carrying cost is Rs.4 per
piston per year. Find (a) Economic order quantity (b) Maximum inventory.
36. An engineering firm has determined from the analysis of past accounting and production
data that part number 607 has ordering cost of Rs 350 per order and it costs Rs 22 per
part. The inventory carrying cost is 15% of the cost of the item per year. The firm
currently purchases Rs 2, 20,000 worth of this part every year. Determine the economic
order quantity. What is the time between two orders? What is optimum numbers of
orders per year to minimize the cost for the firm?
37. If a product is to be manufactured within the company the details are as follows:
Annual demand rate, r = 24000 units
Production rate, k = 48000 units
Setup cost, C0 = Rs. 200 per setup
Carrying cost, Cc = Rs. 20/unit/year. Find the (i) EOQ and (ii) Cycle time.
38. A product ‘X’ is purchased by a company from outside suppliers. The consumption is
10,000 units per year. The cost of the item is Rs.5 per unit and the ordering cost is
estimated to be Rs.100 per order. The cost of carrying inventory is 25%. If the
consumption rate is uniform, determine the economic purchasing quantity.
39. Find the optimal order quantity for a product for which the price breaks are as follows:
Quantity Unit cost (Rs.)
0 ≤ q1 ≤ 500 10.00
500 ≤ q2 ≤ 750 9.25
750 ≤ q3 8.75
The monthly demand for a product is 200 units, the cost of storage is 2% of the unit cost
and the cost of ordering is Rs. 350.
for service (b) The expected percentage of idle time for each girl (c) If a customer has to
wait, find the expected length of his waiting time.
18. Cars arrive at a petrol pump, having one petrol unit, in Poisson fashion with an average of
10 cars per hour. The service time is distributed exponentially with a mean of 3 minutes.
Find (a) average number of cars in the system (b) average waiting time in the queue. (c)
average queue length (d) the probability that the number of cars in the system is 2.
19. Patients arrive at a clinic to a Poisson distribution at the rate of 30 patients per hour. The
waiting room does not accommodate more than 14 patients. The examination time per
patient is exponential with mean rate of 20 per hour. (a) Find the effective arrival rate at
the clinic. (b) What is the probability that an arriving patient will not wait (c) What is the
expected waiting time until a patient is discharged from the clinic.
20. A manufacturing firm producing refrigerators has given a contract to supply 50 units at
the end of the first month, 50 at the end of the second month, and 50 at the end of the
third. The cost of producing ′X′ number of refrigerators in any month is given by X2. The
firm can produce more members of refrigerators in any month and carry them to the next
month. However, a holding cost of Rs. 20 per unit is charged for any refrigerator carried
over from month to the next. Assuming here is no initial inventory, determine the
number of refrigerators to be produced in each month so as to minimize the total cost,
using dynamic programming approach.
21. A medical representative located at city 1 has to travel to city 10. He knows the distance
of alternative routes from city 1 to city 10 and has drawn the network map based on the
distance between the cities as in the following table. Draw the network and find the
shortest possible route. Also, find the shortest routes from any city to city 10.
From To city Corresponding distance in
city km
1 2, 3, 4 4, 6, 3
2 5, 6, 7 7, 10, 5
3 5, 6, 7 3, 8, 4
4 5, 6, 7 6, 10, 5
5 8, 9 4, 8
6 8, 9 3, 7
7 8, 9 8, 4
8 10 7
9 10 9
22. Use dynamic programming to find the value of
Maximize z = y1y2y3
Subject to the constraints:
Y1 + y2 + y3 = 5
Y1, y2, y3 ≥0
Quiz Questions
18. Customer behaviour in which be moves from one queue to another in a multiple channel
situation is [ ]
(a) Balking (b) reneging (c) jockeying (d) alternating
19. Which of the following characteristics apply to queue system? [ ]
(a) Customer population 9b) Arrival process (c) both (a) and (b) (d) neither (a) and (b)
20. In (M/M/S) : (N/FIFO), which of the following is wrongly stated [ ]
(a) Poisson arrival (b) exponential service (c) single server (d) limited service
21. Which of the following is not considered as the negative behaviour of customer according
to queue discipline [ ]
(a) Reneging (b) jockeying (c) balking (d) boarding
22. At steady state in a queue [ ]
(a) λ > μ (b) λ < μ (c) λ ≤ μ (d) λ ≥ μ
23. SIRO discipline is found generally in __ [ ]
(a) Office filing (b) trains arriving to platform (c) lottery (d) loading and unloading
24. A Poisson arrival, exponential service by single server to limited queue selected randomly
is represented by ______________
(a) (M/E/S) : (α/SIRO) (b) (M/M/S) : (N/SIRO) (c) (M/M/1) : (N/SIRO) (d) (M/M/i) :
(α/SIRO)
25. A doctor rushing to an emergency case leaving his regular service is said to be
(a) Pre-emptive Q discipline (b) non-pre-emptive Discipline (c) reneging (d) Balking
26. A game with more than two players is called ______________________ player game.
27. The value of the game shoes pay off is a 2 × 2 identity matrix is _____________.
28. The game whose pay off is null matrix is ________________ game.
29. If minimax value is same as maximin value the game said to have ______________.
30. The list of all possible actions that will take for every pay off that might results is called
_____________________.
31. If gain of a player is loss of the other then the game is called___________.
34. The gap between the ordering point and its immediate actual stock completion point is
called _______________________
35. First stage decision is solved last in ___________ recursive approach.
36. The algebraic equation that represents the benefits of a decision in DPP is called______
37. The optimality principle is given by_________
38. According optimality principle, if an optimal solution is obtained to a systems it must be
optimal to _______________ of the system.
39. The probabilistic model among replacement policies is _________________
40. Pre paid taxi at an airport follow ___________________ queue discipline
41. The unit of utilization factor is _______________________________
42. If the value of the game is zero, then that game/strategy is known as [ ]
A) Pure strategy B) mixed strategy C) fair game D) pure game
53. A game with more than two players is called ______________________ player game
54. The game whose pay off is null matrix is ________________ game
59. The gap between the ordering point and its immediate actual stock completion point is
called _______________________
Tutorial Problems
Job 1 2 3 4 5 6 7
A 5 7 3 4 6 7 12
B 2 6 7 5 9 5 8
C 10 12 11 13 12 10 11
Tutorial Sheet No. 7 (Individual Replacement Problem)
2. A manufacturer is offered two machines A and B. A has the cost price of Rs. 2,500/- its
running cost is Rs. 400 for each of the first 5 years and increase by Rs.100/- every
subsequent year. Machine B having the same capacity as A. and costs Rs. 1250/-, has
running cost of Rs.600/- for first 6 years, increasing thereby Rs. 100/- per year. Which
machine should be purchased? Scrap value of both machines is negligible. Money value
is 10% per year.
Tutorial Sheet No. 8 (Group Replacement Problem)
1. The following failure rates have been observed for a certain type of light bulb.
End of Week: 1 2 3 4 5 6 7 8
Probability of failure: 0.05 0.13 0.25 0.43 0.68 0.88 0.96 1.00
The cost of replacing an individual bulb is Rs. 2.25. The decision is made to replace all bulbs
simultaneously at fixed intervals, and also to replace individual bulbs as they fail in service.
If the cost of group replacement is 60 paise per bulb and the total number of bulbs is 1,000,
what is the best interval between group replacements?
What are the best strategies for players A and B in this game? What is the value of the game
for A and B?
Tutorial Sheet No. 10 (Theory of Games)
1. Two players P and Q play the game. Each of them has to choose one of the three colours:
White (W), Black (B) and Red (R) independently of the other. Thereafter the colours are
compared. If both P and Q has chosen white (W, W), neither wins anything If player P
selects white and Player Q black (W, B), player P loses Rs.2/- or player Q wins the same
amount and so on. The complete payoff table is shown below. Find the optimum
strategies for P and Q and the value of the game.
Problems: Students are strongly advised to work out all the above problems and problems in
the text-book and do similar problems from the reference books. It is also strongly
recommended that the students should tryout the algorithms on computers to get a better
understanding of the subject.
Note: Lecture notes and solutions to above problems are provided separate document.
Prepared by
Approved by
HoD, ME