rope is 20 meters long. After cutting 6 short skipping ropes of 2.3 meters, how many meters are left?
一根绳长20米，剪下6根2.3米的短跳绳后，还剩多少米？
<gadget id="calculator">6 * 2.3</gadget>
<output>13.8</output>

<gadget id="calculator">20 - 13.8</gadget>
<output>6.2</output>

<result>6.2</result>