This year, the father's age is four times that of Xiaoqiang's, and the sum of their ages is 55, so how old is Xiaoqiang?
今年，父亲年龄是小强年龄的4倍，两人年龄和是55岁，那么小强是多少岁．
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">55 / 5</gadget>
<output>11</output>

<result>11</result>