The numerator of (5/8) is increased by 15, how many times should the denominator be enlarged to keep the fraction size constant
(5/8)的分子增加15，要使分数大小不变，分母应扩大多少倍
<gadget id="calculator">5 + 15</gadget>
<output>20</output>

<gadget id="calculator">20 / 5</gadget>
<output>4</output>

<result>4</result>