If roosters are less than hens (1/4), then hens are much more than roosters.
如果公鸡比母鸡少(1/4)，那么母鸡就比公鸡多多少．
<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">4 * (3/4)</gadget>
<output>3</output>

<gadget id="calculator">4 - 3</gadget>
<output>1</output>

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

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