设油菜籽X,，西红柿籽Y和萝卜籽Z3X+4Y+1/7Z=100-----1式X+Y+Z=100-----2式100之内7的倍数有7,14,21,28,35,42,49,56,63,70,77,84,91,98.(Z值)而7,14,21,28,35,42,49,56,63,70代入1.2式最小值大于100. 98代入1.2式最大值小于100.解得z=30, y=0,z=70或X＝3，Y＝20，Z＝77．－＿－
