<script >function sum() {    var txtFirstNumberValue = document.getElementById('studentenrolled').value;    var txtSecondNumberValue = document.getElementById('classsize').value;    var result = parseInt(txtFirstNumberValue) / parseInt(txtSecondNumberValue);    if (!isNaN(result)) {       document.getElementById('nooftut').value = result;    }}</script>         <tr>         <td><label for="studentenrolled">Student Enrolled</label>  </td>        <td> <input type="text" name="studentenrolled" id="studentenrolled"  value="<?php echo $row['studentenrolled']; ?> " /></td>         </tr>                       <tr>         <td><label for="classsize">Class Size</label>  </td>         <td> <input type="text" id="classsize"  onkeyup="sum();" /></td>         </tr>         <tr>        <td><label for="nooftut">No Of Tutorial</label>  </td>        <td> <input type="text" id="nooftut" disabled="disabled" /></td>        </tr> 如何在“nooftut”計算中向上或向下舍入結果：studentenrolled / class size = nooftut 由于 studentenrolled 是從數據庫中提取的，我無法向上或向下舍入