There is a chicken farm. All the chicken in that farm need a total of at least 8 kg of protein, 12 kg of fat, and 6 kg of fiber, to stay healthy. Two brands of foods, A and B, are used to feed the chicken. each kg of brand A contains 10 grams of protein, 25 grams of fat, and 24 grams of fiber, each kg of brand B contains 60 grams of protein, 50 grams of fat and 8 grams of fiber. Each kg of brand A is bought with the cost of RM2.50, whereas each kg of brand B is bought with the cost of RM2.00. Determine the amount (in kg, decimals allowed) of brand A and brand B needed supply all essential nutrients to the chicken, yet keeping the total cost to the minimum. Also determine such minimum cost.