1、西师大版二年级数学上册,4的乘法口诀,重庆市云阳县 冉崇兵,准备题,每辆车有4个车轮,3辆车一共有多少个车轮?,43= (个),34= (个),三四十二,12,12,每辆车有4个车轮。算一算,填一填。,汽车(辆),车轮(个),4,5,6,7,8,9,16,每辆车有4个车轮。算一算,填一填。,汽车(辆),车轮(个),4,5,6,7,8,9,16,20,每辆车有4个车轮。算一算,填一填。,汽车(辆),车轮(个),4,5,6,7,8,9,16,20,24,每辆车有4个车轮。算一算,填一填。,汽车(辆),车轮(个),4,5,6,7,8,9,16,20,24,28,每辆车有4个车轮。算一算,填一填。,汽
2、车(辆),车轮(个),4,5,6,7,8,9,16,20,24,28,32,每辆车有4个车轮。算一算,填一填。,汽车(辆),车轮(个),4,5,6,7,8,9,16,20,24,28,32,36,4个4得16,4416,四四十六,5个4得20,4520,四五二十,6个4得24,4624,四六二十四,7个4得28,4728,四七二十八,8个4得32,4832,四八三十二,9个4得36,4936,四九三十六,4个4得16,4416,四四十六,5个4得20,4520,四五二十,6个4得24,4624,四六二十四,7个4得28,4728,四七二十八,8个4得32,4832,四八三十二,9个4得36,4
3、936,四九三十六,3的乘法口诀有哪些特征和规律?,3的乘法口诀共有6句。,口诀的第一个字都是四。,口诀的第二个字从上到下 依次增加1。,口诀的积从上到下依次 增加4。,算一算。,48=,54=,四八三十二,32,四五二十,20,各用哪句口诀算?,1、摆小棒,填算式,说口诀。,=,4,2,=,2,4,二四得八,8,8,1、摆小棒,填算式,说口诀。,=,4,3,=,3,4,三四十二,12,12,1、摆小棒,填算式,说口诀。,=,4,4,四四十六,16,1、摆小棒,填算式,说口诀。,=,4,5,=,5,4,四五二十,20,20,1、摆小棒,填算式,说口诀。,=,4,6,=,6,4,四六二十四,24
4、,24,1、摆小棒,填算式,说口诀。,=,4,7,=,7,4,四七二十八,28,28,1、摆小棒,填算式,说口诀。,=,4,8,=,8,4,四八三十二,32,32,1、摆小棒,填算式,说口诀。,=,4,9,=,9,4,四九三十六,36,36,47,64,94,42,54,43,84,41,2、对口令。,3,6,12,4,8,16,5,10,20,6,12,24,7,14,28,8,16,32,9,18,36,3、游戏。,1、填空。,4,=,16,20,24,4,5,6,9,8,7,4=,36,32,28,2、把口诀填完整。,五,三,四,四( )二十,( )六十八,三( )十二,八,四,九,三
5、( )二十四,( )八三十二,三 ( )二十七,七,四,四,四( )二十八,( )九三十六,( )四十六,3、计算。,71=,62=,38=,26=,7,12,24,12,53=,93=,27=,54=,15,27,14,20,82=,48=,39=,73=,16,32,27,21,4、过河。,5、(1)4张这样的书桌,有多少个抽屉?,12,34 (个),三四十二,5、(2)4张这样的书桌,有多少扇门?,8,24 (个),二四得八,5、(3)4张这样的书桌,有多少条腿?,16,44 (个),四四十六,6、分别把4乘1,2,3,9的积圈起来。,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,10,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,36,49 (人),答:能坐36人。,7、每桌坐4人,能坐多少人?,有9张空桌。,