If there are more boys than girls (1/4), then there are fewer girls than boys.
若男生人数比女生多(1/4)，则女生人数就比男生少多少．
<gadget id="calculator">4 / 1</gadget>
<output>4</output>

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

<gadget id="calculator">5 - 4</gadget>
<output>1</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>