Question

67x67x99的简便方法

• 你的回答被采纳后将获得：
• 系统奖励15（财富值+成长值）+难题奖励20（财富值+成长值）

Answer 1

67x67x99
=67x67x100-67x67
=(60+7)x(70-3)x100-67x67
=(4200+490-180-21)x100-67x67
=(4200+490-180-21)x100-67x67
=4489x100-67x67
=4489x100-4489
=440000+8900-4500+11
=444411
67x67x99=67x67x9x11=67x(603)x11=(70-3)x(600+3)x11=(42000-1800+210-9)x11
=(42000-2000+200+200+10-9)x11
=40401x11
=444411