A bundle of iron wire is 30 meters long, 8.15 meters are used for the first time, and 7.85 meters are used for the second time, how many meters are left?
一捆铁丝长30米，第一次用去8.15米，第二次用去7.85米，还剩多少米？
<gadget id="calculator">8.15 + 7.85</gadget>
<output>16</output>

<gadget id="calculator">30 - 16</gadget>
<output>14</output>

<result>14</result>