A manufacturer makes two types of rubber, Butadiene and Polyisoprene. The plant has two machines, Machine-1 and Machine-2, and both of them are used to make the rubber strips. Machine-1 is available 180 hours per month and Machine-2 is available 200 hours per month. Manufacturing one strip of Butadiene requires 2.75 hours on Machine-1 and 3 hours on Machine-2. For processing one strip of Polyisoprene, it takes 3.5 hours on Machine-1 and 4 hours on Machine-2.
a. Formulate an all-integer model that will determine how many units of each type of the rubber should be used to maximize the manufacturer’s contribution to profit if he gets a profit of $20 on Butadiene and $26 on Polyisoprene?
b. Use Excel Solver to determine the optimal number of units produced of each type of rubber (Butadiene and Polyisoprene).