《整百、整千数加减法》教学课件1.ppt
整百、整千数加减法,万以内数的认识,1.口算。,4050 90608050 60302070 1090 6020 10070,复习,90,30,90,30,90,100,30,40,2.填一填。,(1)80里面有()个十;150里面有()个十。(2)500里面有()个百;1300里面有()个百。(3)4000里面有()个千;10000里面有()个千。(4)2000里面有()个千;2000里面有()个百。,8,15,5,13,4,10,2,20,探究新知,用加法计算:,100020003000(元),1个千,2个千,3个千,探究新知,用加法计算:,100020003000(元),1 2 3,用减法计算:,200010001000(元),探究新知,9006001500600,8050,130,13050,80,想加法:50()130,13050,80,80,1500,900,试一试。,8个十加5个十是13个十,就是130。,探究新知,7050 800900 12050 1700900,200400 30006000 600400 90003000,1.计算。,知识运用,600,200,9000,6000,120,70,1700,800,2.捉鼠竞赛。,4000,160,80,75030,13001000,540260,4200300,6300500,4600400,75030,13001000,540260,4200300,6300500,4600400,3.算一算,并说一说你是怎样算出来的。,780,2300,800,4500,6800,5000,720,300,280,3900,5800,4200,(1)迎宾山庄和假日宾馆一共住了多少人?,4.桂林山水美,喜迎天下人。,9006001500(人),4.桂林山水美,喜迎天下人。,(2)民俗度假村比假日宾馆多住了多少人?,20006001400(人),4.桂林山水美,喜迎天下人。,(3)你还能提出哪些数学问题?你会解答吗?,课堂作业,作业:第97页练习十九,第3题。第98页练习十九,第4题。,