如题所述
第1个回答 2020-02-25
11✘99
=11x(100-1)
=11x100-11
=1100-11
=1089
=11x(100-1)
=11x100-11
=1100-11
=1089
第2个回答 2022-12-11
乘法分配律为:两个数的和与一个数相乘,先将它们与这个数分别相乘,再相加,积不变.即:(a+b)×c=a×c+b×c.反过来则:a×c+b×c=(a+b)×c
11×99
= 11× ( 100-1)
= 100×11-11
= 1100-11
= 1089
11×99
= 11× ( 100-1)
= 100×11-11
= 1100-11
= 1089
第3个回答 2020-02-25
11X99
=11x(99+1)
=11x100-11
=1100-11
=1089
=11x(99+1)
=11x100-11
=1100-11
=1089
第4个回答 2020-02-25
原式=10x99+99
=990+99
=1089
=990+99
=1089
第5个回答 2020-02-25
11×99
=11×(100-1)
=11×100-11
=1089
=11×(100-1)
=11×100-11
=1089