,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,两位数减两位数,退位减,1,.,2024/11/17,两位数减两位数1.2023/10/6,82,-,10=,2,.,2024/11/17,82-10=2.2023/10/6,15-3=,3,.,2024/11/17,15-3=3.2023/10/6,46-20=,4,.,2024/11/17,46-20=4.2023/10/6,49-6=,5,.,2024/11/17,49-6=5.2023/10/6,36-30=,6,.,2024/11/17,36-30=6.2023/10/6,19-7=,7,.,2024/11/17,19-7=7.2023/10/6,28-4=,8,.,2024/11/17,28-4=8.2023/10/6,76-5=,9,.,2024/11/17,76-5=9.2023/10/6,37-7=,10,.,2024/11/17,37-7=10.2023/10/6,96-20=,11,.,2024/11/17,96-20=11.2023/10/6,86-70=,12,.,2024/11/17,86-70=12.2023/10/6,67-4=,13,.,2024/11/17,67-4=13.2023/10/6,29-20=,14,.,2024/11/17,29-20=14.2023/10/6,56-30=,15,.,2024/11/17,56-30=15.2023/10/6,74-4=,16,.,2024/11/17,74-4=16.2023/10/6,17,.,2024/11/17,17.2023/10/6,巴黎比北京少多少票？,巴黎,18,票,北京,56,票,56,18,18,.,2024/11/17,巴黎比北京少多少票？巴黎18票北京56票561818.2,十,个,56,18,个位上,6,减,8,不够减，,怎么办？,还剩多少根,？,38,19,.,2024/11/17,十个5618个位上6减8不够减，还剩多少根3819.20,个,十,5 6,1 8,3,8,个位上,6,减,8,不够减，,从十位退,1,，个位变,成,16,8,。,如果个位不够减，就从十位退,1,。,16,4,56,18,38,20,.,2024/11/17,个十5 6 1 838个位上6减8不够减，如果个位不够,50,24,26,个,十,5 0,2 4,2,6,个位上,0,减,4,不够减，,从十位退,1,后，,个位要算,（）减（）。,10,4,从十位退,1,后，,十位要算,（）减（）。,4,2,1.,相同数位要对齐；,2.,从个位减起；,3.,如果个位不够减，就从十位退,1,。,21,.,2024/11/17,502426个十5 0 2 426 个位上0减4不,22,.,2024/11/17,22.2023/10/6,练习三,5.,先用小棒摆一摆，再计算。,23,.,2024/11/17,练习三5.先用小棒摆一摆，再计算。23.2023/10/6,练习三,6.,下面的计算对吗？把错误的改正过来。,24,.,2024/11/17,练习三6.下面的计算对吗？把错误的改正过来。24.2023,=25,=18,=12,=8,=13,=17,25,.,2024/11/17,=25=18=12=8=13=1725.2023/10/6,43,33,23,45,25,5,76,46,16,55,15,5,26,.,2024/11/17,433323452557646165515526.2023/,80,800,60,600,80,800,27,.,2024/11/17,80800606008080027.2023/10/6,计,算,28,.,2024/11/17,计28.2023/10/6,74,28,46,38,51,45,23,60,造房子,29,.,2024/11/17,7428463851452360造房子29.,笔算两位数减两位数，要记住三条：,1.,相同数位对齐；,2.,从个位减起；,3.,个位不够减，从十位退,1,，,在个位上加,10,再减。,30,.,2024/11/17,笔算两位数减两位数，要记住三条：1.相同数位对齐；2.从个位,31,.,2024/11/17,31.2023/10/6,4846=,4 8,4 6,0 2,02,2,2,32,.,2024/11/17,4846=0 202 2232.2023/10/6,4929=,4 9,2 9,2,2,2 0,20,33,.,2024/11/17,4929=222 02033.2023/10/6,3 6,36,5,8 1,81,86 5=,8 6,34,.,2024/11/17,3 63658 18186 5=34.2023/10/,课堂总结,通过今天的学习，你学会了什么？,35,.,2024/11/17,课堂总结35.2023/10/6,