The school bought 161 meters of plastic rope, cut 21 meters, and made 12 skipping ropes. According to this calculation, how many skipping ropes can be cut from the remaining plastic ropes.
学校买来161米塑料绳子，剪下21米，做12根跳绳，照这样计算，剩下的塑料绳还可以剪多少根跳绳．
<gadget id="calculator">161 - 21</gadget>
<output>140</output>

<gadget id="calculator">12 * 140</gadget>
<output>1_680</output>

<gadget id="calculator">1_680 / 21</gadget>
<output>80</output>

<result>80</result>