The fare of a taxi company in a certain city is stipulated as follows: within 3 kilometers, all charges are 9 yuan, and for distances exceeding 3 kilometers, the fee is 2.4 yuan per kilometer. Lao Li took a taxi from home to the train station and paid 81 yuan. , How far is Lao Li's house from the train station?
某市出租车公司运费是这样规定的：3千米以内一律收9元，超出3千米的路程，每千米收费2.4元，老李从家乘出租车去火车站，付车费81元，老李家离火车站有多远？
<gadget id="calculator">81 - 9</gadget>
<output>72</output>

<gadget id="calculator">72 / 2.4</gadget>
<output>30</output>

<gadget id="calculator">30 + 3</gadget>
<output>33</output>

<result>33</result>