Add 15 to the numerator of (3/5), how many times should its denominator be enlarged
(3/5)的分子加上15，它的分母应该扩大多少倍
<gadget id="calculator">15 / 3</gadget>
<output>5</output>

<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<result>6</result>