Add 8 to the numerator of (4/11), how much should be added to the denominator to keep the fraction value unchanged
(4/11)的分子加上8，要使分数值不变，分母应加上多少
<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<gadget id="calculator">3 * 11</gadget>
<output>33</output>

<gadget id="calculator">33 - 11</gadget>
<output>22</output>

<result>22</result>