40 students in the second class of the fifth grade planted 104 trees in total. Each girl planted 3 trees, and each boy planted 2 trees. How many girls are there in the second class of the fifth grade?
五年级二班40名同学种树，共种104棵，每个女生种3棵，每个男生种2棵，五年级二班有几名女生？
<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<gadget id="calculator">104 - 80</gadget>
<output>24</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<gadget id="calculator">24 / 1</gadget>
<output>24</output>

<result>24</result>