99X99十9的简便方法怎么做
1个回答
关注
展开全部
99 × 99 + 9 = 9 × (11 × 99 + 1) = 9 × (1089 + 1) = 9 × 1090 = 9810
咨询记录 · 回答于2021-11-18
99X99十9的简便方法怎么做
您好!请问是99×99+9还是99×99+99?
99 × 99 + 9 = 9 × (11 × 99 + 1) = 9 × (1089 + 1) = 9 × 1090 = 9810