最新课件冀教版数学二年级下册《整百数加减》PPT课件.ppt
整百数加减,冀教版二年级数学下册,1(1)13个十是多少?(2)25个百是多少?(3)5个千呢?(4)80里面有()个十。,2700里面有()个百。130里面有()个十。4000里面有()个千。,400300,3,想:4个百加3个百是7个百,700,700300,400,20006000,8000,90004000,5000,9个千减去4个千等于5个千,20030,4,23030,230200,练一练,20030,2个百加上3个十等于2个百3个十,也就是230,230,返回,200,23030,200,30,返回,30,230200,200,30,返回,练一练,200400=30006000=90007000=45050=45004000=3400400=,8050,5,13050,13080,8个十加5个十是13个十就是130。,130,因为8050等于130,所以130减去80就等于50。,80,因为8050等于130,所以130减去50就等于80。,50,9006001500600,1500,900,练一练,70504006008009001205010006001400800,巩固练习。,1口算下面各题。,2接力赛看算得又对又快,2接力赛看算得又对又快。,900300540300290080020005000640200720020043003005200200360360,作业。,2接力赛看算得又对又快,1口算(3分钟完成)70050030002000700010004005070002000400500600500905030002000170080012007003607046005005070063030,2直接写出答案。5003070001000=55050=7002006030370804500200708072020,3扩展题。(1)()350750400()80()70210280()780(2)菜店有萝卜350千克,卖了一些,还剩80千克,卖了多少千克?,4用10、20、3080八个数,分别填在小圆圈里,使每个大圈上五个数的和等于210。,