Add 8 to the numerator of (2/3), to keep the size of the fraction unchanged, add the amount to the denominator
(2/3)的分子加上8，要使分数的大小不变，分母就加上多少
<gadget id="calculator">3 * 5</gadget>
<output>15</output>

<gadget id="calculator">15 - 3</gadget>
<output>12</output>

<result>12</result>