第1单元 第1课时 连加、连减 （课件PPT）-【优翼·学练优】2022-2023学年二年级数学上册同步备课（苏教版）

苏教版二年级上册 连加、连减 第一单元·100以内的加法和减法(三) www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 1 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 情境导入 三人一共折了多少只? 我折了27只。 我折了19只。 我折了26只。 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 新知探究 想一想先算什么,再接着往下算。 19 + 27 ? ? + 26 ? ? ? ? 4 6 7 2 4 6 1 1 还可以这样写 19 + 27 ? ? 4 6 1 + 26 ? ? 7 2 1 这两种计算方法有什么不同？？你认为哪种写法比较简便？ 1 9 + 2 7 + 2 6 = 72 () 只 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 试一试 可以怎样写竖式？ 90 - 25 ? ? - 28 ? ? ? ? 6 5 3 7 6 5 还可以这样写 90 - 25 ? ? 6 5 - 28 ? ? 3 7 90－25－28= 37 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 想想做做 35 + 24 ? ? 5 9 + 17 ? ? 7 6 93 - 58 ? ? 3 5 - 17 ? ? 1 8 1. 1 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 想想做做 23+36+27= 86 45+28+16= 89 92-44-23= 25 50-25-25= 0 85-29-38= 18 32+32+32= 96 详解 详解 详解 详解 详解 详解 【点击详解可见具体解题过程】 2. www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 想想做做 【点击详解可见具体解题过程】 ？人 3. + 37 48 + 14 = 99 详解 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com 想想做做 （1）一共摘了多少个？ （2）运走60个，还剩多少个？ 4. 38 + 46 = 84 () 个 84 － 60 = 24 () 个 答：一共摘了84个。 答：还剩24个。 www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.com www.youyi100.