The experimental middle school planted 576 trees this year, which is 12 times that of last year. How many trees were planted by the experimental middle school last year?
实验中学今年植树576棵，是去年的12倍，实验中学去年植树多少棵？
<gadget id="calculator">576 / 12</gadget>
<output>48</output>

<result>48</result>