Xiaohong has a 1-meter-long rope. She cuts 40 centimeters for the first time and 3 decimeters for the second time. How long is the rope?
小红有一根1米长的绳子，第一次剪去40厘米，第二次剪去3分米，这根绳子还有多长？
<gadget id="calculator">1 * 100</gadget>
<output>100</output>

<gadget id="calculator">3 * 10</gadget>
<output>30</output>

<gadget id="calculator">100 - 40 - 30</gadget>
<output>30</output>

<result>30</result>