A certain class of boys is 40% of the whole class, and the number of girls is the number of the whole class.
某班男生是全班的40%，女生人数是全班的多少．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

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