- 20 Marks
Question
Assume that the management of Community Bank Limited wants to invest up to N100,000 in inventory considered to be either conservative or speculative. The company’s board-approved investment policy is that the investment in conservative inventory should be at most N80,000, while the investment in the speculative inventory should be at least N12,000. Assume further that N1.6 return is expected on each naira invested in the conservative inventory, N2.0 return is expected on each investment in the speculative inventory, and that monetary policy regulations require that investment in the speculative inventory should be at most one-third of the investment in the conservative inventory.
Required:
a. State the type of Operations Research problem described above. (2 Marks)
b. Formulate mathematically the:
i. Objective function. (4 Marks)
ii. Constraint inequalities. (8 Marks)
iii. Investment problem. (6 Marks)
(Total: 20 Marks)
Answer
(a) Type of Operations Research Problem:
The problem described is a Linear Programming Problem (LPP), which aims to optimize (maximize) returns on inventory investments under given constraints. (2 Marks)
(b) Mathematical Formulation:
Let:
- CCC: Investment in conservative inventory (in naira)
- SSS: Investment in speculative inventory (in naira)
(i) Objective Function:
The objective is to maximize the total return on investments in both conservative and speculative inventories.
Maximize Z=1.6C+2.0S
Where:
- 1.6C : Return on investment in conservative inventory
- 2.0S2 : Return on investment in speculative inventory
(4 Marks)
(ii) Constraint Inequalities:
The constraints can be formulated as follows:
- Total Investment Constraint:
C+S ≤ 100,000The total investment should not exceed N100,000.
- Conservative Investment Constraint:
C ≤ 80,000 The investment in conservative inventory should be at most N80,000.
- Speculative Investment Constraint:
S ≥ 12,000The investment in speculative inventory should be at least N12,000.
- Monetary Policy Regulation:
The investment in speculative inventory should be at most one-third of the investment in conservative inventory.
- Non-negativity Constraints:
C ≥ 0, S ≥ 0(8 Marks)
(iii) Investment Problem:
The investment problem is to determine the values of C and S that maximize the total return (Z), subject to the above constraints. Mathematically:
Maximize Z = 1.6C + 2.0S
- Monetary Policy Regulation:
C+S ≤ 100,000 (available fund constraint)
C ≤ 80,000 (Conservative investment policy constraint
C ≥ 12,000 (Speculative investment policy
C ≤ 1/3 x (monetary policy constraint)
Non negativity/hidden constraint C,S ≥ 0

- Tags: Constraints, Inventory Management, Investment policy, Linear Programming, Optimization
- Level: Level 1
- Topic: Operations Research
- Series: NOV 2015
- Uploader: Dotse