Discussion:
Decision variables, objective function, and all the constraints
A woman wants to set up a trust fund for her two children using $200,000. The trust fund has three investment options: a bond fund, a stock fund, and treasury bills fund. The projected returns over the life of the investments are 6% for the bond fund, 10% for the stock fund, and 8% for the treasury bills fund. She wants to invest at least 30% of the total amount in the bond fund, at least 20% in the stock fund, and at least 25% in the treasury bills fund. She also wants the amount invested in the treasury bills fund to be less than or equal to the amount invested in the stock fund. She wants to know how much should be invested in each of the three alternatives to maximize the total projected returns.
Formulate a linear programming model by defining decision variables, objective function, and all the constraints.