3.9+39.9+399.9+3999.9用简便算法

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/12 16:14:04

3.9+39.9+399.9+3999.9用简便算法
3.9+39.9+399.9+3999.9用简便算法

3.9+39.9+399.9+3999.9用简便算法
3.9+39.9+399.9+3999.9
=(4-0.1)+(40-0.1)+(400-0.1)+(4000-0.1)
=(4+40+400+4000)-(0.1+0.1+0.1+0.1)
=4444-0.4
=4443.6

解: 3.9+39.9+399.9+3999.9
=(4-0.1)+(40-0.1)+(400-0.1)+(4000-0.1)
=4+40+400+4000-0.4
=4444-0.4
=4443.6
祝你开心

3333+(0.9+9.9+99.9+999.9)
=3333+1+10+100+1000-0.1*4
=4444-0.4
=4443.6