Known 2: x=(1/2):(1/4), then x=how much
已知2：x=(1/2)：(1/4)，则x=多少
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 * (1/4)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) / (1/2)</gadget>
<output>1</output>

<result>1</result>