The sum of the ages of the four people is 77 years old. The youngest is 10 years old. The sum of his and the oldest age is 7 years older than the sum of the ages of the other two. What is the age of the oldest.
四个人年龄之和是77岁．最小的10岁，他与最大的年龄之和比另外二人年龄之和大7岁，最大的年龄是多少岁．
<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>