The porcelain shop entrusted the portering station to transport 800 vases. The two parties agreed that the shipping fee for each vase was 0.35 yuan. How many vases were broken?
瓷器商店委托搬运站运送800只花瓶，双方商定每只运费是0.35元，如果打破一只，不但不计运费，而且要赔偿2.50元，结果运到目的地后，搬运站共得运费268.6元，求打破了多少只花瓶？
<gadget id="calculator">800 * 0.35</gadget>
<output>280</output>

<gadget id="calculator">280 - 268.6</gadget>
<output>11.4</output>

<gadget id="calculator">0.35 + 2.5</gadget>
<output>2.85</output>

<gadget id="calculator">11.4 / 2.85</gadget>
<output>4</output>

<result>4</result>