A table earns a profit of R1,800 and a chair, R1,500. If the carpenter produces tables, he has to bear a fixed cost of R24,000. Likewise, if the carpenter produces chairs, he must bear a fixed cost of R20,000. The store wants to determine the number of tables and chairs it needs to produce to maximize profit.

a. Formulate an integer programming model for this problem.

b. Solve this model by using the computer.