There are 50 students in Class 51, including 21 girls. What percentage of the class are boys?
五1班有学生50人，其中有女生21人，男生占全班人数的几分之几？
<gadget id="calculator">50 - 21</gadget>
<output>29</output>

<gadget id="calculator">29 / 50</gadget>
<output>29/50 = around 0.58</output>

<result>29/50 = around 0.58</result>