rope is 300 meters long, 126 meters are used for the first time, and 36 meters are used less than the first time for the second time. How many meters is the rope now shorter than before?
一根绳子长300米，第一次用去126米，第二次比第一次少用去36米，现在这根绳子比原来短多少米．
<gadget id="calculator">126 - 36</gadget>
<output>90</output>

<gadget id="calculator">90 + 126</gadget>
<output>216</output>

<result>216</result>