A store operates a kind of schoolbag, its cost is 42 yuan each, and the ratio of the profit from selling one to the turnover is 5:12, if the store makes a profit of 300 yuan by selling this kind of schoolbag in a certain week, then this How many schoolbags did you sell last week?
某商店经营一种书包，它的成本是每个42元，卖出一个所得的利润与营业额之比为5：12，如果某周内该店卖这种书包获得了300元利润，那么这周卖出了几个书包？
<gadget id="calculator">12 / 5</gadget>
<output>12/5 = around 2.4</output>

<gadget id="calculator">300 * (12/5)</gadget>
<output>720</output>

<gadget id="calculator">720 - 300</gadget>
<output>420</output>

<gadget id="calculator">420 / 42</gadget>
<output>10</output>

<result>10</result>