Xuexue saw that Taishang Laojun was using a rope to tie the treasure gourd. The first time he used half of the total length was 2 meters longer, the second time he used the remaining half 10 meters less, and the third time he used 15 meters. , there are 9 meters left in the end, so how many meters is the original rope?
学学看到太上老君正在用一根绳子拴宝葫芦，第一次用去全长的一半还多2米，第二次用去余下的一半少10米，第三次用去15米，最后还剩9米，那么这根绳子原来有多少米．
<gadget id="calculator">15 - 10</gadget>
<output>5</output>

<gadget id="calculator">9 + 5</gadget>
<output>14</output>

<gadget id="calculator">14 * 2</gadget>
<output>28</output>

<gadget id="calculator">28 + 2</gadget>
<output>30</output>

<gadget id="calculator">30 * 2</gadget>
<output>60</output>

<result>60</result>