1 / 9

运算定律与 简算的整理

运算定律与 简算的整理. 找一找：谁和谁是好朋友？. 72. 51. 178. 125. 25. 263. 28. 163. 49. 8. 22. 4. 想一想，横线上应该填什么会使计算更加简便？你是怎么想的？. 25×137×. 4. 125×61×. 8. 练习一：简便计算. 107+158+93+42 487-139-61 （125+40）×8 25×44 3200÷25÷4 66×101-66.

benedict-estes
Download Presentation

运算定律与 简算的整理

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 运算定律与 简算的整理

  2. 找一找：谁和谁是好朋友？ 72 51 178 125 25 263 28 163 49 8 22 4

  3. 想一想，横线上应该填什么会使计算更加简便？你是怎么想的？想一想，横线上应该填什么会使计算更加简便？你是怎么想的？ 25×137× 4 125×61× 8

  4. 练习一：简便计算 107+158+93+42 487-139-61 （125+40）×8 25×44 3200÷25÷4 66×101-66 同桌之间相互交流一下，每道题分别运用了什么运算定律？

  5. 练习二： 25×444 25×444 =25×（400+40+4） =10000+1000+100 =11100 =25×4×111 =100×111 =11100

  6. 练习三：改错 8×50×2×125 =8×125+50×2 =1000+100 =1100 8×50×2×125 =(8×125)×(50×2) =1000×100 =100000

  7. 102×89 =（100+2）×89 =89×100+2 =8902 102×89 =（100+2）×89 =89×100+2×89 =8900+178 =9078

  8. 练习四： 李大爷家有一块菜地（如下图），这块菜地的面积有多少平方米？ 8米 21米 19米 8米

  9. 思考： 小明在计算（□+50）×4时，算成 □×4+50，他的计算结果和正确结果相比，怎么样？

More Related