NATIONAL OPEN UNIVERSITY OF NIGERIA
14/16 AHMADU BELLO WAY, VICTORIA ISLAND, LAGOS
SCHOOL OF SCIENCE AND TECHNOLOGY
MARCH/APRIL 2014 EXAMINATION
COURSE CODE: CIT 425
COURSE TITLE: OPERATIONS RESEARCH
TIME ALLOWED: 2HOURS
INSTRUCTION:ANSWER ANY FOUR QUESTIONS
1. (a) What is Linear Programming. Enumerate at least five assumptions in Linear Programming. (7 Marks)
(b) TRAX Ships a certain refrigerator unit from factories in Lagos and Onitsha to distribution
centres in Abuja and Kano. Shipping costs are summarized in the table below:
| Source | Destination | Shipping Cost |
| Lagos | Abuja Kano | N30 N40 |
| Onitsha | Abuja Kano | N60 N50 |
The supply and demand, in number of units, is shown below:
| Supply | Demand |
| Lagos, 200 Onitsha, 600 | Abuja, 300 Kano, 400 |
How should transportation issue be made from Lagos and Onitsha to minimize the transportation cost? (13 Marks)
2. (a) Explain the terms;Modeling and Models. (4 Marks)
(b) List and explain five classes of mathematical model. (6 Marks)
(c) The sales manager of Turnover Limited maintains he could increase the sales turnover
(in units) of any of the company’s product by 50 percent if he was authorized to give a 10%
price discount and place appropriate additional advertising matter. The Board wishes to know
the maximum additional advertising expense they can incur in respect of any given product
without the manager’s proposal resulting in a smaller profit. (10 Marks)
3. (a) Using a tabular form, summarize the various common prototypes, their nature, model and
the techniques for handling each of these prototypes. (8 Marks)
(b) A convalescent hospital wishes to provide at a minimum cost, a diet that has a minimum of
of carbohydrates, of protein and of fats per day. These requirements can
be met with two foods:
| Food | Carbohydrates | Protein | Fats |
| A | |||
| B |
If food A cost per ounce and food B cost per ounce, how many ounces of each food should be purchased for each patient per day in order to meet the minimum requirements at the lowest cost?
Formulate the Linear Programming model. (12 Marks)
4. (a) State and explain the principle of Optimality (5 Marks)
(b) A company presently operates three manufacturing plants that distribute a product to four
warehouses. Currently, the capacity of the plants and the demands of the warehouses are
stable. These are listed with the unit shipping costs in the following table.
Find the optimal distribution plan for the company (15 Marks)
| PLANTS | WAREHOUSES A B C D | MONTHLY CAPACITY | |||
| X | 3 | 16 | 9 | 2 | 40 |
| Y | 1 | 9 | 3 | 8 | 20 |
| Z | 4 | 5 | 2 | 5 | 50 |
| Monthly Demands | 25 | 25 | 42 | 8 | 110 100 |
5. (a) What is Operation Research. Discuss. (4 Marks)
(b) List and explain three approaches in the analysis and interpretation of business problem. (7 )
(c) Enumerate and briefly explain the various steps involved in the scientific approach to an
operation research problem. (9 Marks)
6. (a) Explain Vogel’s Approximation Method, outlining the algorithm involved in this method. (7)
(b) A manufacturing company has divided its total target market into three zones.
The Company’s marketing department has been collecting data regarding the
deployment of salesmen and the sales made in each zones. They have realized that
the sales are directly dependent upon the number of salesmen in each zone.
The data collected by the company is given in the table below. For various reasons, the
company has decided to retain only 9 salesmen during the next year.
Determine the allocation of these salesmen to these three different zones, so that the total
sales cab net is maximized. (13 Marks)
| No. of Salesmen | Profits in Thousands of Naira | ||
| Zone 1 | Zone 2 | Zone 3 | |
| 0 | 35 | 40 | 45 |
| 1 | 40 | 50 | 50 |
| 2 | 45 | 65 | 60 |
| 3 | 60 | 75 | 70 |
| 4 | 70 | 85 | 80 |
| 5 | 80 | 95 | 90 |
| 6 | 90 | 100 | 100 |
| 7 | 105 | 105 | 110 |
| 8 | 100 | 100 | 120 |
| 9 | 90 | 105 | 100 |
For the 2015 – till date past questions for this course CLICK HERE
Contact me for your TMA, GST302 Business plan writeup, Project Writeup and also get your Exam Summary for this course.
