下面各题怎样简便就怎样算.
来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/11/11 05:00:33
下面各题怎样简便就怎样算. 101×99 | 25×32×25 |
(125+50)×8 | 11.91+8.59+20.09 |
44.5×4+55.5×4 | 4.64-2.36-1.64-0.24. |
(1)101×99
=(100+1)×99
=100×99+1×99
=9900+99
=9999;
(2)25×32×25
=25×4×8×25
=(25×4)×(8×25)
=100×200
=20000;
(3)(125+50)×8
=125×8+50×8
=1000+400
=1400;
(4)11.91+8.59+20.09
=11.91+20.09+8.59
=32+8.59
=40.59;
(5)44.5×4+55.5×4
=(44.5+55.5)×4
=100×4
=400;
(6)4.64-2.36-1.64-0.24
=(4.64-1.64)-(2.36+0.24)
=3-2.6
=0.4.
=(100+1)×99
=100×99+1×99
=9900+99
=9999;
(2)25×32×25
=25×4×8×25
=(25×4)×(8×25)
=100×200
=20000;
(3)(125+50)×8
=125×8+50×8
=1000+400
=1400;
(4)11.91+8.59+20.09
=11.91+20.09+8.59
=32+8.59
=40.59;
(5)44.5×4+55.5×4
=(44.5+55.5)×4
=100×4
=400;
(6)4.64-2.36-1.64-0.24
=(4.64-1.64)-(2.36+0.24)
=3-2.6
=0.4.