解:99x99+9等于( 9810 )
∵已知需求出99x99+9等于多少
A × (B + C)= A × B + A × C
∴99 × 99 + 9
= 9 × (11 × 99 + 1)
= 9 × (1089 + 1)
= 9 × 1090
= 9810
答:99x99+9等于9810
9.9+9.9*99
=9.9*(99+1)
=9.9*100
=990
99*999+999
=99*999+1*999
=(99+1)*999
=100*999
=99900.
拿起手机里,打开界面。点击计算器。迅速点下99乘99加九
原式=9.9*(1+99)
=9.9*100
=99