The sum of the ages of the four people is 77 years old, the youngest of them is 10 years old, and the sum of the ages of him and the oldest is 7 years older than the sum of the ages of the other two, so how old is the oldest among these four people?
四个人的年龄之和为77岁，其中年龄最小的为10岁，他与最大的年龄之和比另外两人年龄之和大7岁，则这四人中，年龄最大的人为多少岁．
<gadget id="calculator">77 - 7</gadget>
<output>70</output>

<gadget id="calculator">1 + 1</gadget>
<output>2</output>

<gadget id="calculator">70 / 2</gadget>
<output>35</output>

<gadget id="calculator">7 - 10</gadget>
<output>-3</output>

<gadget id="calculator">35 + (-3)</gadget>
<output>32</output>

<result>32</result>