There are 50 students in Class 1 of five years, including 30 male students. What percentage of the total number of female students are in the class?
五年一班有学生50人，其中男同学有30人，女同学人数占全班人数的几分之几？
<gadget id="calculator">50 - 30</gadget>
<output>20</output>

<gadget id="calculator">20 / 50</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>