Xiao Ming is 9 years old this year, and his father is 4 years older than 3 times Xiao Ming's age. How old is dad?
小明今年9岁，爸爸今年的年龄比小明年龄的3倍大4岁．爸爸今年多少岁？
<gadget id="calculator">9 * 3</gadget>
<output>27</output>

<gadget id="calculator">27 + 4</gadget>
<output>31</output>

<result>31</result>