Two foods, I and II, containing the following % of carbohydrates, protein and fat:
Food carbohydrates protein fat
1 40% 50% 6%
2 60% 20% 4%
Food 1 costs $3 per gram, and food 2 costs $4 per gram. Find the amount of each that should be served to produce at least ten grams of carbohydrates, 7.5 grams of protein and 1.2 grams of fat, if cost is to be minimized.