苏教版数学四年级上册学程单1. 括号里最大能填几?30 ( )6120 ( )126 ( )80 33050 ( )1402. 笔算。484 1656 933 3. 算式: 想一想:如何口算 列一列:竖式1. 括号里最大能填几30 ( )6120 ( )126( )80 33040 ( )2102 64 52. 笔算484 1656 933 9 33 3 19 30 312276 314 84 1 24 80 81656 27 12 45 3 426020203=606020=362=36020=360 里面有3 个20 ,所以6020=31 3 2=3 (包)答:60 副陆战棋要打3 包。想一想:如何口算?6020=3 (包)答:60 副陆战棋要打3 包。列一列:竖式42= 93=4020= 9030= 217= 408= 21070= 40080=22333355我会口算我是口算大王320 40= 80 20= 7010= 45050 = 35070= 18060 = 300 60= 24040 = 720 90= 63070 = 10020 = 4010 = 9030 = 160