There are 240 boys in Shilin Primary School, and 500 girls, three times as many as boys. How many girls are there in Shilin Primary School?
石林小学有男生240人，女生人数是男生的3倍少500人．石林小学有女生多少人？
<gadget id="calculator">240 * 3</gadget>
<output>720</output>

<gadget id="calculator">720 - 500</gadget>
<output>220</output>

<result>220</result>