Solution ratio. (3/4): X=3:12.
解比例．(3/4)：X=3：12．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">3 / 12</gadget>
<output>1/4 = around 0.25</output>

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

<result>3</result>