Dahua Glass Store entrusts the handling station to deliver 500 glass bottles. The two parties agreed that the shipping fee for each piece was 0.48 yuan. If one piece was broken, not only would the shipping fee not be paid for this piece, but the compensation would be 2.52 yuan. Question: How many glass bottles were broken during transportation?
大华玻璃店委托搬运站运送500只玻璃瓶．双方商定每只运费是0.48元，如果打破一只，这一只不但不给运费，而且还要赔偿2.52元，结果搬运站共得运费231元．问：搬运中打破了几只玻璃瓶？
<gadget id="calculator">500 * 0.48</gadget>
<output>240</output>

<gadget id="calculator">240 - 231</gadget>
<output>9</output>

<gadget id="calculator">0.48 + 2.52</gadget>
<output>3</output>

<gadget id="calculator">9 / 3</gadget>
<output>3</output>

<result>3</result>