大九九乘法口诀表19

6 × 1 = 6 6 × 2 = 12 6 × 3 = 18 6 × 4 = 24 6 × 5 = 30

6 × 6 = 36 7 × 1 = 7 7 × 2 = 14 7 × 3 = 21 7 × 4 = 28 7 × 5 = 35 7 × 6 = 42 7 × 7 = 49 8 × 1 = 8 8 × 2 = 16 8 × 3 = 24 8 × 4 = 32 8 × 5 = 40 8 × 6 = 48 8 × 7 = 56 8 × 8 = 9 × 1 = 9 9 × 2 = 18 9 × 3 = 27 9 × 4 = 36 9 × 5 = 45 9 × 6 =

9 × 7 = 63 9 × 8 = 72 9 × 9 = 81 10 × 1 = 10 10 × 2 = 20 10 × 3 = 30 10 × 4 = 40 10 × 5 = 50 10 × 6 = 60 10 × 7 = 70 10 × 8 = 80 10 × 9 = 90 10 × 10 = 100

11 × 1 = 11 11 × 2 = 22 11 × 3 = 33 11 × 4 = 44 11 × 5 = 55 11 × 6 = 66 11 × 7 = 77 11 × 8 = 88

11 × 9 = 99 11 × 10 = 110 11 × 11 = 121 12 × 1 = 12 12 × 2 = 24 12 × 3 = 36 12 × 4 = 48 12 × 5 = 60 12 × 6 = 72 12 × 7 = 84 12 × 8 = 96 12 × 9 = 108 12 × 10 = 120 12 × 11 = 132 12 × 12 = 144 13 × 1 = 13 13 × 2 = 26 13 × 3 = 39 13 × 4 = 52 13 × 5 = 65 13 × 6 = 78 13 × 7 = 91

13 × 8 = 104 13 × 9 = 117 13 × 10 = 130 13 × 11 = 143 13 × 12 = 156 13 × 13 = 169 14 × 1 = 14 14 × 2 = 28 14 × 3 = 42 14 × 4 = 56 14 × 5 = 70 14 × 6 = 84 14 × 7 = 98 14 × 8 = 112 14 × 9 = 126 14 × 10 = 140 14 × 11 = 1 14 × 12 = 168 14 × 13 = 182 14 × 14 = 196 15 × 1 = 15 15 × 2 = 30

15 × 3 = 45 15 × 4 = 60 15 × 5 = 75 15 × 6 = 90 15 × 7 = 105 15 × 8 = 120 15 × 9 = 135 15 × 10 = 150 15 × 11 = 165 15 × 12 = 180 15 × 13 = 195 15 × 14 = 210 15 × 15 = 225

16 × 1 = 16 16 × 2 = 32 16 × 3 = 48 16 × 4 = 16 × 5 = 80 16 × 6 = 96 16 × 7 = 112 16 × 8 = 128

16 × 9 = 144 16 × 10 = 160 16 × 11 = 176 16 × 12 = 192 16 × 13 = 208 16 × 14 = 224 16 × 15 = 240 16 × 16 = 256 17 × 1 = 17 17 × 2 = 34 17 × 3 = 51 17 × 4 = 68 17 × 5 = 85 17 × 6 = 102 17 × 7 = 119 17 × 8 = 136 17 × 9 = 153 17 × 10 = 170 17 × 11 = 187 17 × 12 = 204 17 × 13 = 221 17 × 14 = 238

17 × 15 = 255 17 × 16 = 272 17 × 17 = 2 18 × 1 = 18 18 × 2 = 36 18 × 3 = 18 × 4 = 72 18 × 5 = 90 18 × 6 = 108 18 × 7 = 126 18 × 8 = 144 18 × 9 = 162 18 × 10 = 180 18 × 11 = 198 18 × 12 = 216 18 × 13 = 234 18 × 14 = 252 18 × 15 = 270 18 × 16 = 288 18 × 17 = 306 18 × 18 = 324 19 × 1 = 19

19 × 2 = 38 19 × 3 = 57 19 × 4 = 76 19 × 5 = 95 19 × 6 = 114 19 × 7 = 133 19 × 8 = 152 19 × 9 = 171 19 × 10 = 190 19 × 11 = 209 19 × 12 = 228 19 × 13 = 247 19 × 14 = 266 19 × 15 = 285 19 × 16 = 304 19 × 17 = 323 19 × 18 = 342 19 × 19 = 361 20 × 1 = 20 20 × 2 = 40 20 × 3 = 60 20 × 4 = 80

20 × 5 = 100 20 × 6 = 120 20 × 7 = 140 20 × 8 = 160 20 × 9 = 180 20 × 10 = 200 20 × 11 = 220 20 × 12 = 240 20 × 13 = 260 20 × 14 = 280 20 × 15 = 300 20 × 16 = 320 20 × 17 = 340 20 × 18 = 360 20 × 19 = 380 20 × 20 = 400

大九九乘法口诀表的意义

19×19乘法口诀是速算课的一个学习重点，为什么要背19×19口诀？熟背19×19口诀，不仅可以提高孩子的数算能力，而且可以锻炼孩子的思考力、分析力和创造力。数学强国印度的小朋友能把19×19口诀倒背如流，因此，他们在国际数学竞赛中总有出色的表现，在制作电脑软件的领域，无人能与其相比，印度在信息技术领域具有雄厚实力的原因，也许可以从19×19口诀找到。 19×19口诀具体作用如下：

一、加快多位数的乘法运算

如果是两位数的乘法运算，可以直接运用19×19口诀。举例来说，运算235×19，如果是只背诵九九乘法口诀的小朋友，就需要分别计算235×10和235×9。而背诵了19×19口诀的小朋友，却可以一步算出，事半功倍。

二、加法、减法、除法运算也会神奇地变快了

256÷16是多少呢？只背诵九九乘法口诀的小朋友需要动手进行计算，而背诵了19×19口诀，就可以在看到题目的一

瞬间就明白答案是16。因为16×16=256已经牢牢地定格在大脑里了。

三、约数和倍数，理解数的性质

小学高级段的学生已经学习了像约数、倍数这样一个具有某种性质的数，就是学习数与数之间的关系。背过19×19口诀以后，285=15×19就会立刻在脑子里出现。我们也就理解了285这个数的性质。285既是15的倍数，也是19的倍数；反过来，285的约数中有15和19。

四、分数运算既快速又轻松

举个例子，2/15 +3/17，必须将分母15和17进行通分，通分过程中包括下列计算：15×17=255，2×17=34，3×15=45，如果背好了19×19口诀，就可以立刻计算出答案了，在学习19×19口诀的过程中，还可以帮助我们更好地理解约数和倍数的性质，分数计算也就变容易啦。

学生充分了解了背诵的价值，就开始兴致勃勃地背诵啦！为了能让孩子们更轻松更快的背下来，我想了很多方法。先把口诀分为11×1到19×19两个阶段来进行练习，首先练习

并背诵19×9段，然后再到19×19段，并套用了多个旋律明显、朗朗上口的儿歌、童谣进行练习，孩子们有了极大的兴趣，又采用了多种快算方法帮助记忆，还有卡片游戏、规律总结、联系九九乘法口诀等等方法来帮助孩子背诵。付出有了收获，经过短短的几节课，每一期的孩子绝大多数都可以很熟练地做到见题报数。

相信背会了19×19口诀，会给孩子们以后的学习带来意想不到的收获！