Xiao Ming chatted with his grandfather, Xiao Ming said: "The age difference between you and Dad is exactly three times my age." Grandpa smiled and said: "The combined ages of your father and son are still 18 years behind me!" So how old is Xiao Ming this year? age.
小明和爷爷聊天，小明说："您和爸爸的年龄差恰好是我年龄的3倍．"爷爷笑笑说："你们父子俩的年龄加起来还跟我差18岁呢!"那么小明今年多少岁．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<result>9</result>