For a ratio, if the former item is increased by 30%, the latter must be added with a ratio of 3 to keep it unchanged. What is the latter of this ratio?
一个比如果将前项增加30%，后项必须加上3比值才能不变，这个比的后项是多少．
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">3 / (3/10)</gadget>
<output>10</output>

<result>10</result>