A rope is 86 meters long, 38 meters are used for the first time, and 29 meters are used for the second time. How much is the length of the rope shortened now? what is the correct formula
一根绳子长86米，第一次用去38米，第二次用去29米，现在绳子的长度比原来缩短了多少米？正确的算式是多少
<gadget id="calculator">38 + 29</gadget>
<output>67</output>

<result>67</result>