There are 30 boys and 20 girls in our class. What percentage of the whole class are boys?
我们班有男生30人，女生20人，男生人数占全班人数的几分之几？
<gadget id="calculator">30 + 20</gadget>
<output>50</output>

<gadget id="calculator">30 / 50</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>