In 5:4, if 10 is added to the former term, how much should be added to the latter term to keep the ratio constant
在5：4中，如果前项加上10，要使比值不变，后项要加上多少
<gadget id="calculator">10 / 5</gadget>
<output>2</output>

<gadget id="calculator">2 * 4</gadget>
<output>8</output>

<result>8</result>