There were 41 blue schoolbags in the store, and 30 green schoolbags were purchased. A total of 39 schoolbags were sold today, how many schoolbags are left in the store now?
商店里原有蓝书包41个，又购进绿书包30个．今天共卖出书包39个，现在商店还剩多少个书包？
<gadget id="calculator">30 - 39</gadget>
<output>-9</output>

<gadget id="calculator">41 + (-9)</gadget>
<output>32</output>

<result>32</result>