The sum of the ages of the four people is 84 years old, the youngest is 5 years old, and the sum of his and the oldest age is 8 years younger than the sum of the ages of the other two people. What is the age of the oldest person?
四个人年龄之和是84岁，最小的5岁，他与最大的年龄之和比另外两个人年龄之和小8岁，最大的年龄是多少岁．
<gadget id="calculator">84 - 8</gadget>
<output>76</output>

<gadget id="calculator">76 / 2</gadget>
<output>38</output>

<gadget id="calculator">38 - 5</gadget>
<output>33</output>

<result>33</result>