A senior home has snacks of spinach and soybeans to increase their intake of iron. A cup of spinach contains 100 units of fibre and 5 mg of iron. A cup of soybeans contains 80 units of fibre and 12 mg of iron. Due to other nutritional requirements, the nurses decided that the number of cups of spinach must exceed the number of cups of soybeans. Furthermore, a cup of spinach contains 30 calories while a cup of soybeans contains 100 calories. If they schedule that the elderly need in total at least 12000 units of fibre and 300 mg of iron, how many cups of each should the nurses schedule to maximize the seniors’ total caloric intake?