This year, my father is 43 years old and my son is 11 years old. How many years later, the age of the father is three times the age of the son.
今年爸爸43岁，儿子11岁．多少年后爸爸的年龄是儿子年龄的3倍．
<gadget id="calculator">43 - 11</gadget>
<output>32</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">32 / 2</gadget>
<output>16</output>

<gadget id="calculator">16 - 11</gadget>
<output>5</output>

<result>5</result>