The school sports team bought a bundle of ropes for skipping. The first time they used half of the total length, more than 6 meters, the second time they used the remaining half less than 10 meters, the third time they used 12 meters, and finally there were 15 meters left. How many meters is the bundle of rope?
学校体育组买了捆绳子做跳绳，第一次用去全长的一半多6米，第二次用去余下的一半少10米，第三次用去12米，最后还剩15米，这捆绳子原来有多少米？
<gadget id="calculator">12 - 10</gadget>
<output>2</output>

<gadget id="calculator">15 + 2</gadget>
<output>17</output>

<gadget id="calculator">17 * 2</gadget>
<output>34</output>

<gadget id="calculator">34 + 6</gadget>
<output>40</output>

<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<result>80</result>