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LP Ch.02: Introduction to Linear Programming

Transform your complex business challenge into an optimized plan of action—powered by Gurobi’s world-leading solver technology.

Blog

LP Ch.02: Introduction to Linear Programming

Transform your complex business challenge into an optimized plan of action—powered by Gurobi’s world-leading solver technology.

Blog

LP Ch.02: Introduction to Linear Programming

Transform your complex business challenge into an optimized plan of action—powered by Gurobi’s world-leading solver technology.

In this article, we will explore linear programming through the lens of the Furniture Factory Problem. By formulating this problem as a linear programming model, we can maximize total revenue while respecting resource constraints. So let's dive into the details and learn how linear programming can be applied to solve real-world problems.

The Furniture Factory Problem

Imagine a furniture factory that produces chairs and tables. The goal is to develop a production plan that maximizes the total revenue while considering the available resources. The following information is provided:

Selling price of a chair: \$45

Selling price of a table: \$80

Available resources:

Mahogany: 400 units

Labor: 450 hours

The data scientist estimates the resource requirements for each product:

One chair requires 5 units of mahogany and 10 hours of labor.

One table requires 20 units of mahogany and 15 hours of labor.

Decision Variables

To create a production plan, we need to determine the number of chairs (x1) and the number of tables (x2) to produce. These decision variables represent the quantities we can control to maximize revenue. For this problem, x1 and x2 must be non-negative values (greater than or equal to 0).

Objective Function

The objective is to maximize the total revenue generated by the production of chairs and tables. The revenue from chairs can be calculated as 45x1, where 45 represents the selling price per chair. Similarly, the revenue from tables is 80x2, where 80 represents the selling price per table. Therefore, the objective function is:

Maximize: Revenue = 45x1 + 80x2

Resource Constraints

To ensure the production plan does not exceed the available resources, we impose constraints on mahogany and labor capacity.

Mahogany constraint

The total amount of mahogany consumed by chairs and tables combined should not exceed the available 400 units. Considering 5x1 as the mahogany consumption for chairs and 20x2 as the consumption for tables, the constraint can be expressed as:5x1 + 20x2 ≤ 400

Labor constraint

The total labor consumed by chairs and tables combined should not exceed the available 450 hours. With 10x1 representing the labor consumption for chairs and 15x2 for tables, the constraint can be expressed as:10x1 + 15x2 ≤ 450

Non-Negative Constraint

To maintain the feasibility of the production plan, the decision variables x1 and x2 must be non-negative:

x1, x2 ≥ 0

Final Linear Programming Formulation

Taking into account the objective function, resource constraints, and non-negative constraint, the Furniture Factory Problem can be formulated as a linear programming problem:

Maximize: Revenue = 45x1 + 80x2

Subject to:

5x1 + 20x2 ≤ 400 (Mahogany constraint)

10x1 + 15x2 ≤ 450 (Labor constraint)

x1, x2 ≥ 0 (Non-negative constraint)

Conclusion

Linear programming offers a systematic approach to solving optimization problems, such as the Furniture Factory Problem. By formulating the problem as a linear programming model, we can determine the optimal production plan that maximizes revenue while considering resource limitations. In this article, we introduced the concept of linear programming, explained the Furniture Factory Problem, and provided a step-by-step guide on formulating the problem mathematically. With this understanding, you can explore advanced techniques and algorithms to solve more complex real-world problems using linear programming.

Resources

Download the linear programming tutorial slides.

View the entire series:

  1. Welcome: Linear Programming Tutorial

  2. Chapter 1: Mathematical Programming

  3. Chapter 2: Introduction to Linear Programming

  4. Chapter 3: Mixed Integer Linear Programming Problems

  5. Chapter 4: Furniture Factory Problem

  6. Chapter 5: Simplex Method

  7. Chapter 6: Modeling and Solving Linear Programming Problems

  8. Chapter 7: Sensitivity Analysis of Linear Programming Problems

  9. Chapter 8: Multiple Optimal Solutions

  10. Chapter 9: Unbounded Linear Programming Problems

  11. Chapter 10: Infeasible Linear Programming Problems

  12. Chapter 11: Linear Programming Overview - Further Considerations

  13. Chapter 12: Duality in Linear Programming

  14. Chapter 13: Optimality Conditions

  15. Chapter 14: Dual Simplex Method

Start Solving with Gurobi

Try Gurobi on your own optimization models and see how it performs on real decision problems.

Start Solving with Gurobi

Try Gurobi on your own optimization models and see how it performs on real decision problems.

Start Solving with Gurobi

Try Gurobi on your own optimization models and see how it performs on real decision problems.