楼主你好!
此题用的是乘法分配率的逆运算
99×28+28
=99×28+1×28
=(99+1)×28
=100×28
=2800
望楼主采纳关注!关注可私信我告诉你很多!
99×28+28 =99 ×28+1×28=(99+1)×28=100×28=2800
99×28+28
=99×28+1×28
=(99+1)×28
=100×28
=2800
99×28 十28
=(99 十1)×28
=100*28
=2800
99×28+28
=99×28+1×28
=(99+1)×28
=100×28
=2800