Question: A product P is to be blended from three ingredients I1, I2, and I3. Firm requirements dictate that at least 100 lbs of P are to be blended, and that the average cost of the blend per pound do not exceed $2.80, given that one pound of the three ingredients costs $5, $3, and $2 for I1, I2, and I3, respectively. In addition, it would be desirable if 20 % of P were to be I1. Similarly, the decision maker would like to have P consist of no more than 50 % of the cheap ingredient I3, if possible. This desirable feature is about half as important as the former desirable feature. Formulate as a goal programming problem.