[原创]超简单的计算方法哦~~~可以教宝宝哦
<p><font color="#ff0000"><strong>1.</strong><strong>十几乘十几</strong></font><b></b></p><p><font color="#008000"><strong>口诀:头乘头,尾加尾,尾乘尾。</strong><b></b></font></p>
<p><font color="#008000"><strong>例:</strong><strong>12×14=</strong><strong>?</strong><b></b></font></p>
<p><font color="#008000"><strong>解</strong><strong>: 1×1=1</strong><b></b></font></p>
<p><font color="#008000"><strong> </strong><strong>2+4=6</strong><b></b></font></p>
<p><font color="#008000"><strong>2</strong><strong>×</strong><strong>4=8</strong><b></b></font></p>
<p><font color="#008000"><strong>12×14=168</strong><b></b></font></p>
<p><font color="#008000"><strong>注:个位相乘,不够两位数要用</strong><strong>0</strong><strong>占位。</strong></font> </p>
<p><font color="#ff0000"><strong>2</strong><strong>.</strong><strong>头相同,尾互补</strong><strong>(</strong><strong>尾相加等于</strong><strong>10)</strong><strong>:</strong><b></b></font></p>
<p><font color="#008000"><strong>口诀:一个头加1后,头乘头,尾乘尾。</strong><b></b></font></p>
<p><font color="#008000"><strong>例:</strong><strong>23×27=</strong><strong>?</strong><b></b></font></p>
<p><font color="#008000"><strong>解:2+1=3</strong><b></b></font></p>
<p><font color="#008000"><strong> </strong><strong> </strong><strong>2</strong><strong>×</strong><strong>3=6</strong><b></b></font></p>
<p><font color="#008000"><strong> </strong><strong> </strong><strong>3</strong><strong>×</strong><strong>7=</strong><strong>21</strong><b></b></font></p>
<p><font color="#008000"><strong> 23×27=621</strong><b></b></font></p>
<p><font color="#008000"><strong>注:个位相乘,不够两位数要用</strong><strong>0</strong><strong>占位。</strong></font><b></b></p>
<p><font color="#ff0000"><strong>3</strong><strong>.</strong><strong>第一个乘数互补,另一个乘数数字相同:</strong></font><b></b></p>
<p><font color="#008000"><strong>口诀:一个头加1后,头乘头,尾乘尾。</strong><b></b></font></p>
<p><font color="#008000"><strong>例:</strong><strong>37×44=</strong><strong>?</strong><b></b></font></p>
<p><font color="#008000"><strong>解:</strong><strong>3+1=4</strong><b></b></font></p>
<p><font color="#008000"><strong> 4×4=16</strong><b></b></font></p>
<p><font color="#008000"><strong> 7×4=28</strong><b></b></font></p>
<p><font color="#008000"><strong> 37×44=1628</strong><b></b></font></p>
<p><font color="#008000"><strong>注:个位相乘,不够两位数要用</strong><strong>0</strong><strong>占位。</strong></font><b></b></p>
<p><font color="#ff0000"><strong>4</strong><strong>.</strong><strong>几十一乘几十一:</strong><b></b></font></p>
<p><font color="#008000"><strong>口诀:头乘头,头加头,尾乘尾。</strong><b></b></font></p>
<p><font color="#008000"><strong>例:</strong><strong>21×41=</strong><strong>?</strong><b></b></font></p>
<p><font color="#008000"><strong>解:</strong><strong>2×4=8</strong><b></b></font></p>
<p><font color="#008000"><strong> 2+4=6</strong><b></b></font></p>
<p><font color="#008000"><strong> 1×1=1</strong><b></b></font></p>
<p><font color="#008000"><strong> 21×41=861</strong><b></b></font></p>
<p><font color="#ff0000"><strong>5</strong><strong>.11</strong><strong>乘任意数:</strong><b></b></font></p>
<p><font color="#008000"><strong>口诀:首尾不动下落,中间之和下拉。</strong><b></b></font></p>
<p><font color="#008000"><strong>例:</strong><strong>11×23125=</strong><strong>?</strong><b></b></font></p>
<p><font color="#008000"><strong>解:</strong><strong>2+3=5</strong><b></b></font></p>
<p><font color="#008000"><strong> 3+1=4</strong><b></b></font></p>
<p><font color="#008000"><strong> 1+2=3</strong><b></b></font></p>
<p><font color="#008000"><strong> 2+5=7</strong><b></b></font></p>
<p><font color="#008000"><strong> 2</strong><strong>和</strong><strong>5</strong><strong>分别在首尾</strong><b></b></font></p>
<p><font color="#008000"><strong> 11×23125=254375</strong><b></b></font></p>
<p><strong><font color="#008000">注:和满十要进一。</font></strong><b></b></p>
<p><font color="#ff0000"><strong>6</strong><strong>.</strong><strong>十几乘任意数:</strong><b></b></font></p>
<p><font color="#008000"><strong>口诀:第二乘数首位不动向下落,第一因数的个位乘以第二因数后面每一个数字,</strong><b></b></font></p>
<p><font color="#008000"><strong> </strong><strong>加下一位数,再向下落。</strong><b></b></font></p>
<p><font color="#008000"><strong>例:</strong><strong>13×326=</strong><strong>?</strong><b></b></font></p>
<p><font color="#008000"><strong>解:</strong><strong>13</strong><strong>个位是</strong><strong>3</strong><b></b></font></p>
<p><font color="#008000"><strong> 3×3+2=11</strong><b></b></font></p>
<p><font color="#008000"><strong>3×2+6=12</strong><b></b></font></p>
<p><font color="#008000"><strong> 3×6=18</strong><b></b></font></p>
<p><font color="#008000"><strong> 13×326=4238</strong><b></b></font></p>
<p><font color="#008000"><strong> </strong><strong>注:和满十要进一。</strong> <b></b></font></p>
<p><br/><br/><br/> </p> 自己先沙发一下 不错 记着给宝宝用。谢谢了 <p>不错,收藏,以后教宝宝用</p>
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