2019春一年級數學下冊 6.1《整十數加、減整十數》課件2 (新版)新人教版.ppt
,整十數加、減整十數,引入,口算:,304922866560870444,34,80,65,78,40,90,新授,探究一,探究二,探究三,探究一:,探究一,探究二,探究三,探究一:,探究一,探究二,探究三,探究一:,探究一,探究二,探究三,探究二:,探究一,探究二,探究三,紅花和黃花一共有多少盆?,探究一,探究二,探究三,探究二:,10,20,探究一,探究二,探究三,探究二:,1020,30,探究一,探究二,探究三,探究二:,1020,1個十加上2個十是3個十。,30,探究一,探究二,探究三,探究二:,1020,想:1+2=3,30,探究一,探究二,探究三,探究二:,1020,想:1+2=3,30,1個十加上2個十是3個十。,探究一,探究二,探究三,探究二:,擺一擺,算一算。,3040,70,探究一,探究二,探究三,探究二:,試一試。,105070302040801030304040,60,60,60,100,90,80,探究三:,探究一,探究二,探究三,還有多少盆紫花?,探究三:,探究一,探究二,探究三,30,10,探究三:,探究一,探究二,探究三,3010,20,探究三:,探究一,探究二,探究三,3010,20,3個十減去1個十是2個十。,探究三:,探究一,探究二,探究三,3010,20,想:3-1=2,探究三:,探究一,探究二,探究三,3010,20,探究三:,探究一,探究二,探究三,試一試。,30,30,30,5020804060309010704010060,40,80,40,探究三:,探究一,探究二,探究三,說一說,都是怎樣算的?,102030301020,在計算整十數加、減整十數時,可以直接把十位上的數相加、減。,練習,練習一,練習二,練習三,練習一:,1.口答。,703090307010501060107030502050210070,100,40,70,60,70,52,80,40,30,練習一,練習二,練習三,練習一:,2、,32456430204506040,5,50,9,90,2,20,練習一,練習二,練習三,30474,30470(),練習一:,3.下面的計算正確嗎?把錯誤的改過來。,練習一,練習二,練習三,30470,95590,練習一:,3.下面的計算正確嗎?把錯誤的改過來。,練習一,練習二,練習三,(),95545,練習一:,4、想一想,算一算。,28098820809880307010090703199,82,100,90,18,100,73,10,10,練習一,練習二,練習三,308090108020565,60,80,50,練習二:,1.動腦筋,中填幾?,100,練習一,練習二,練習三,練習三:,練習一,練習二,練習三,練習三:,根據圖中的信息,你能提出那些數學問題?,練習一,練習二,練習三,練習三:,還剩幾個花生?,50102020(個),練習一,練習二,練習三,練習三:,小猴一共吃掉幾個花生?,201030(個),練習一,練習二,練習三,小結:,小結:,計算整十數的加、減法,可以直接把十位上的數相加或相減。,作業(yè):,