Làm quen với biểu thức số
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</div><p></p> <p><strong>Ví dụ về biểu thức số:</strong></p> <p>381+135&nbsp; ;&nbsp; 95-17&nbsp; ;&nbsp; 13x3;&nbsp; 64:8 ;<br>265-82+10&nbsp; ;&nbsp; 11x3+4&nbsp; ;&nbsp; 5x12:2 ;&nbsp; 93:3-20 ;... là các biểu thức số (hay còn gọi tắt là biểu thức).</p> <h3 id="1-doc-caacutec-bieu-thuc-sau-theo-mau">1. Đọc các biểu thức sau (theo mẫu):</h3> <table style="border-collapse: collapse; width: 76.2938%; height: 156.69px;" border="1"> <tbody> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;"><strong>Biểu thức</strong></td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;"><strong>Đọc là</strong></td> </tr> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;">21 + 18</td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;">Hai mươi mốt cộng mười tám</td> </tr> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;">95 - 17</td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;">?</td> </tr> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;">13 x 3</td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;">?</td> </tr> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;">64 : 8</td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;">?</td> </tr> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;">65 - 42 + 10</td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;">?</td> </tr> <tr style="height: 22.3843px;"> <td style="width: 36.081%; text-align: center; height: 22.3843px;">11 x 3 + 4</td> <td style="width: 63.9194%; text-align: center; height: 22.3843px;">?</td> </tr> </tbody> </table> <h3 id="2-chon-caacutech-doc-tuong-ung-voi-moi-bieu-thuc">2. Chọn cách đọc tương ứng với mỗi biểu thức:</h3> <p><img style="display: block; margin-left: auto; margin-right: auto;" src="/uploads/tinymce/b41-h2-1664631428.jpg.webp" width="648" height="284" alt="hinh-anh-lam-quen-voi-bieu-thuc-so-1092-1" title="hinh-anh-lam-quen-voi-bieu-thuc-so-1092-1" loading="lazy"></p> <h3 id="3-hatildey-lap-caacutec-bieu-thuc">3. Hãy lập các biểu thức:</h3> <p>a) Hiệu của 21 trừ đi 3.</p> <p>b) Thương của 21 chia cho 3.</p> <p>c) Tổng của ba số 23, 15 và 40.</p> <p>d) Tích của ba số 5, 2 và 7.</p> <h3 id="4">4.</h3> <p><img style="display: block; margin-left: auto; margin-right: auto;" src="/uploads/tinymce/b41-h3-1664631576.jpg.webp" width="594" height="247" alt="hinh-anh-lam-quen-voi-bieu-thuc-so-1092-2" title="hinh-anh-lam-quen-voi-bieu-thuc-so-1092-2" loading="lazy"></p> <p>Dựa vào hình vẽ trên, nêu ý nghĩa của mỗi biểu thức sau:</p> <p>a) 8 + 9</p> <p>b) 8 + 6</p> <p>c) 8 + 9 + 6</p>