   </td>
</tr>
<tr>
<td>
                  <p>
                    median
                  </p>
                </td>
<td>
                  <p>
                    &#189;(a+b)
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    mode
                  </p>
                </td>
<td>
                  <p>
                    x &#8712; [a, b], so raises domain_error (returning NaN).
                  </p>
                </td>
</tr>
<tr>
<td>
               