Bag A contains a kilogram of rice a, and bag B contains a kilogram of rice b. If 8 kilograms are poured from bag A to bag B, then the two bags of rice weigh the same. In the following quantitative relationship, ab=how much does not meet the meaning of the question.
甲袋有大米a千克，乙袋有大米b千克，如果从甲袋倒出8千克给乙袋，那么两袋大米同样重．下面的数量关系中，a-b=多少不符合题意．
<result>8</result>