(3/4): x = (1/4): (3/8).
(3/4)：x=(1/4)：(3/8)．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">(3/4) * (3/8)</gadget>
<output>9/32 = around 0.28125</output>

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

<gadget id="calculator">(9/32) / (1/4)</gadget>
<output>9/8 = around 1.125</output>

<result>9/8 = around 1.125</result>