- JOSEPH’S COLLEGE OF COMMERCE (AUTONOMOUS)
End Semester Examinations – April 2013
m.com – ii semester
Operations Research for Business Decisions
Duration: 3 Hrs Max. Marks: 100
SECTION – A
- I) Answer any SEVEN Each carries FIVE marks. (7 x 5 = 35)
- The Handy- Dandy company wishes to schedule the production of a kitchen appliance that requires two resources- labour and material. The company is considering three different models and its production engineering department has furnished the following data. Supply of raw material is restricted to 200 Kgs. Per day. The daily availability of labour is 150 hrs. formulate a linear programming model to determine the daily production rate of the various models in order to maximize the total profit. Formulate the problem and write the dual.
Models | |||
A | B | C | |
Labour ( hrs per unit) | 7 | 3 | 6 |
Material ( kgs. Per unit) | 4 | 4 | 5 |
Profit ( Rupees per unit) | 40 | 20 | 30 |
- Use graphical method to solve the following Linear Programming Problem.
Minimize Z= 40x + 36y
Subject to constraints
X<=8
Y<=10
5X + 3Y >=45
Where x, y >=0
- Define Operation Research. Explain the main phases of an OR study.
- Which are the special variables used in Simplex and Big M Method. Explain how and why they are used? What do they indicate?
- Explain the terms: i) feasible solution ii) optimal solution iii) unrestricted variables
- iv) Unbounded solution v) redundancy constraint
- Using least cost method find an initial solution to the transportation problem to maximize profit.
To->
From |
D1 | D2 | D3 | D4 | Availability |
S1 | 40 | 25 | 22 | 33 | 100 |
S2 | 44 | 35 | 30 | 30 | 30 |
S3 | 38 | 38 | 28 | 30 | 70 |
Requirement | 40 | 20 | 60 | 30 |
- In an Assignment problem explain the following special cases
- i) unbalance ii) maximization iii) Prohibited assignment
- iv) multiple optimal solution v) travelling salesman problem
- Give some applications of queuing theory and explain the terms
- i) queue ii) traffic intensity iii) service channel iv) queue discipline v) balking
- A confectioner sells confectionery items. Past data of demand per week in hundred kilograms with frequency is given below:
Demand/week | 0 | 5 | 10 | 15 | 20 | 25 |
Frequency | 2 | 11 | 8 | 21 | 5 | 3 |
Using the following sequence of random numbers, simulate the demand for the next 10 weeks. Also find the average demand per week.
Random Numbers: 35, 52, 90, 13, 23, 73, 34, 57, 37, 83
- Define dynamic programming problem. List and explain the terminologies of dynamic programming problem.
SECTION – B
III) Answer any THREE questions. Each carries FIFTEEN marks. (3×15 = 45)
- Solve the following LPP using Simplex Method
Maximize Z= 3x + 2y
Subject to,
-x +2y <= 4
3x + 2y <=14
X – y <=3
Where x, y >= 0
- Stronghold construction Company is interested in taking loans from banks for some of its projects P, Q, R, S, T. the rates of interest and the lending capacity differ from bank to bank. All these projects are to be completed. The relevant details are provided in the following table. Assuming the role of a consultant, advice this company as to how it should take the loans so that the total interest payable will be the least. Are there alternate optimal solution? If so indicate one such solution.
Bank | Interest rates in
% for projects |
Maximum
Credits ( in thousands) |
||||
P | Q | R | S | T | ||
Pvt. Bank | 20 | 18 | 18 | 17 | 17 | Any amount |
Nationalised Bank | 16 | 16 | 16 | 15 | 16 | 400 |
Co-operative Bank | 15 | 15 | 15 | 13 | 14 | 250 |
Amount required
( in thousands) |
200 | 150 | 200 | 125 | 75 |
- A company has four sales representatives who are assigned to four different sales territories. The monthly sales increase estimated for each sales representative for different sales territories ( in lakh rupees) are shown in the following table. Suggest an optimal assignment and the total maximum sales increase per month. If for certain reasons sales representative ‘B’ cannot be assigned to sales territory III, will the optimal assignment schedule be different? If so find that schedule and effect on total sales.
Sales Territories->
Sales Representatives |
I | II | III | IV |
A | 200 | 150 | 170 | 220 |
B | 160 | 120 | 150 | 140 |
C | 190 | 195 | 190 | 200 |
D | 180 | 175 | 160 | 190 |
- The extension counter of the Citizen’s bank in the premises of a state university enrolls all new customers (students) in savings bank accounts. In the month of August , as the classes begin a lot of new accounts have to be opened for new students enrolled. The bank manager estimates that the arrival rate during this period will be poisson distributed with an average of 3 customers per hour. The service is exponentially distributed with an average of 15 minutes per customer to set up a new account. The bank manager wants to determine the operating characteristics for this system to know whether the current strength of one server is sufficient to handle the increased traffic. Analyse the problem by determining all factors connected with the queueing system.
- Solve the following capital budgeting problem using dynamic programming.
An organization is planning to diversify its business with a maximum outlay of 5 crores. It has identified three different locations to install plants. The organization can invest in one or more of these plants subject to the availability of these funds. The different possible alternatives and their investment (in crores of rupees) and present worth of returns during useful life (in crores of rupees) of each of these plants are summarized in the table. Find the optimal allocation of the capital to different plants which will maximize the corresponding sum of the present worth of returns.
Alternatives | Plant1 | Plant2 | Plant3 | |||
Cost | Return | Cost | Return | Cost | Return | |
1 | 0 | 0 | 0 | 0 | 0 | 0 |
2 | 1 | 15 | 2 | 14 | 1 | 3 |
3 | 2 | 18 | 3 | 18 | 2 | 7 |
4 | 4 | 28 | 4 | 21 | – | – |
Section – C
III) Compulsory Question . (1×20=20)
- The casualty room of a hospital receives between zero and six emergency calls each night according to the following probability distribution.
calls | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
probability | 0.05 | 0.12 | 0.15 | 0.25 | 0.22 | 0.15 | 0.06 |
The medical team at the casualty room classifies each emergency call into one of the three categories: minor, medium or major emergency. The probability that a particular call will be each type of emergency is as below:
Emergency
Type |
Minor | Medium | Major |
Probability | 0.30 | 0.56 | 0.14 |
The type of emergency call determines the size of the medical team scheduled to treat the emergency. A minor emergency requires two person medical team, a medium emergency requires three person medical team and a major emergency requires five person medical team.
Simulate the emergency calls received for 10 nights, compute the average number of each type of emergency call each night and determine the maximum number of medical team members that may be required on any given night.
Random Numbers:
Number of calls during ten nights: 65, 48, 08,05, 89, 06, 62, 17, 77, 68
Emergency type for each call : 71, 18, 12, 17, 89, 18, 83, 90, 18, 08,
26, 47, 94, 72, 47, 68, 60, 88, 36, 43,
28, 31, 06, 39, 71, 22, 76.