My mother is 39 years old this year, and my mother's age is three times that of Xiaohong's. How old is Xiaohong this year?
妈妈今年39岁，妈妈的年龄是小红3倍，小红今年多少岁．
<gadget id="calculator">39 / 3</gadget>
<output>13</output>

<result>13</result>