Add 6 to the numerator of (2/3), how much should the denominator be multiplied to keep the fraction constant?
(2/3)的分子加上6，要使分数大小不变，分母应乘多少
<gadget id="calculator">2 + 6</gadget>
<output>8</output>

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

<result>4</result>