The sum of the ages of the four people is 87 years old, and the youngest is 12 years old. The sum of his and the oldest age is twice the sum of the ages of the other two people. How old is the oldest one?
四个人的年龄之和是87岁，最小的12岁，他与最大年龄之和是另外2人年龄和的两倍，问最大的年龄是多少岁？
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">87 / 3</gadget>
<output>29</output>

<gadget id="calculator">87 - 29 - 12</gadget>
<output>46</output>

<result>46</result>