If girls make up 60% of the class, how many boys make up the class
如果女生人数占全班人数的60%，那么男生人数占全班人数的多少
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

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