Solution ratio 30: x = 2: 0.1, x = how much
解比例30：x=2：0.1，x=多少
<gadget id="calculator">30 * 0.1</gadget>
<output>3</output>

<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<result>3/2 = around 1.5</result>