There are 40 students in class one of the fifth grade, including 21 girls. What percentage of the whole class are girls?
五年级一班有学生40人，其中女生有21人，女生占全班人数的几分之几？
<gadget id="calculator">21 / 40</gadget>
<output>21/40 = around 0.525</output>

<result>21/40 = around 0.525</result>