If the number of girls in a class is less than the number of boys (1/4), then the number of boys is more than the number of girls ((())/(())).
如果某班女生人数比男生人数少(1/4)，那么男生人数比女生人数多((())/(()))．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(1/4) / (3/4)</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>