Moving 1,000 glass bottles, it is stipulated that if one is safely transported, the handling fee will be 0.3 yuan, but if one is broken, not only will the handling fee not be paid, but 0.5 yuan will be paid. If the total shipping fee is 260 yuan after the transportation, how many glass bottles were broken during the transportation?
搬运1000只玻璃瓶，规定安全运到一只可得搬运费0.3元，但打碎一只，不仅不给搬运费，还要赔0.5元．如果运完后共得运费260元，那么，搬运中打碎了几只玻璃瓶？
<gadget id="calculator">1_000 * 0.3</gadget>
<output>300</output>

<gadget id="calculator">300 - 260</gadget>
<output>40</output>

<gadget id="calculator">0.3 + 0.5</gadget>
<output>0.8</output>

<gadget id="calculator">40 / 0.8</gadget>
<output>50</output>

<result>50</result>