My mother is 39 years old, 3 years younger than Niu Niu's age. What is Niuniu's age this year?
妈妈今年39岁，比妞妞年龄的3倍少3岁．妞妞今年的年龄是多少？
<gadget id="calculator">39 + 3</gadget>
<output>42</output>

<gadget id="calculator">42 / 3</gadget>
<output>14</output>

<result>14</result>