There is a batch of chemical fertilizers in the warehouse. The first time you take out (2/5) of the total, the second time you take out 12 bags less than the total (1/3), and there are still 24 bags left in the warehouse. How many bags were taken out twice?
仓库里有一批化肥，第一次取出总数的(2/5)，第二次取出的比总数的(1/3)少12袋，这时仓库里还剩下24袋．两次共取出多少袋？
<gadget id="calculator">24 - 12</gadget>
<output>12</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (2/5) - (1/3)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">12 / (4/15)</gadget>
<output>45</output>

<gadget id="calculator">45 - 24</gadget>
<output>21</output>

<result>21</result>