把 2.9+29.9+299.9+2999.9 简算

来源:学生作业学帮网 编辑:学帮网 时间:2024/05/30 02:35:14

把 2.9+29.9+299.9+2999.9 简算

(3-0.1)+(30-0.1)+(300-0.1)+(3000-0.1)
=3333-0.4
=3332.6

3+30+300+3000—0.1*4
=3332.7

2.9+29.9+299.9+2999.9
=2.9+2.9*10+2.9*100+2.9*1000
=2.9*(1+10+100+1000)
=3221.9

原式=(3-0.1)+(30-0.1)+(300-0.1)+(3000-0.1)=3333-0.4=3332.6

2.9+29.9+299.9+2999.9
=(3-0.1)+(30-0.1)+(300-0.1)+(3000-0.1)
=3+30+300+3000-0.4
=3333-0.4
=3332.6

2.9+29.9+299.9+2999.9
=(3-0.1)+(30-0.1)+(300-0.1)+(3000-0.1)
=3333-0.4
=3332.6