There are 19 students skipping rope on the playground, and 36 students playing sandbags. If the number of people playing sandbags is 6 times the number of rope skippers, how many students who skip rope should be removed?
操场有19个同学跳绳，36个同学打沙包，如果要使打沙包的人数是跳绳人数的6倍，应去掉几个跳绳的同学？
<gadget id="calculator">36 / 6</gadget>
<output>6</output>

<gadget id="calculator">19 - 6</gadget>
<output>13</output>

<result>13</result>