鸡兔同笼，共8个头，20条腿。笼里有几只鸡？几只兔？'r2|+~,L(L9_+|;v:K.G7H/j
算式：提示0`5A+q/h3}2q9n7P0M'r2|+~,L(L9_+|;v:K.G7H/j
答：有6l6Z1d'\)[)?只兔，)l.`/O9c2c+J.E8D8[-Y)}只鸡。'r2|+~,L(L9_+|;v:K.G7H/j