新人教版一年级数学下册十几减九ppt课件.ppt
,二十以内退位减法,十 几 减 九(复习课),9+6=,9+7=,9+3=,15,16,12,9+8=,17,9+4=,13,9+5=,14,9+2=,11,9+( )=12,3,开火车,水果店,我买个。,还剩多少个?,13-9=,4,算一算,有十三颗太阳,拿去九颗太阳。还剩几颗?,13-9=,4,十六只兔子减去九只还剩几只?,16-9=,7,12-9= (只),3,15-9=,6,想:9加( )得15。,6,17-9=,想:9加( )得17。,8,18-9=,9,想:9加( )得18。,9,8,想:10-9= 1+5=,想:10-9= 1+7=,想:10-9= 1+7=,11-9=12-9=13-9=14-9=,15-9=16-9=17-9=18-9=19-9=,2,3,4,5,6,7,8,9,10,仔细观察,你发现了什么?,11 9 = 212 9 = 313 9 = 414 9 = 515 9 = 616 9 = 717 9 = 818 9 = 9,仔细观察,你发现了什么?,11 9 = 2,12 9 = 3,13 9 = 4,14 9 = 5,15 9 = 6,16 9 = 7,17 9 = 8,18 9 = 9,得数只要看十几的个位是几,得数就是比几多1,19 9 = 10,跳木桩,=,给、或=找个家 。 12-9 4 11-9 11+913-3 13-9 18- 9 9,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,179,129,119,169,139,189,13-9,14-9,15-9,胜利,19-9,17-9,12-9,11-9,18-9,20-9,( )-9=5,16-9,入口,+ =14,+ =15,=( ),=( ),=( ),=( ),+ =18,- =2,7,7,7,7,8,9,9,9,9,7,认真想一想,你真棒!,再 见,