The sum of the numerator and denominator of a fraction is 48, and the sum of the fraction is (3/5). What is the difference between the numerator and the denominator of the original fraction?
一个分数的分子与分母的和是48，约分后是(3/5)，原来分数分子与分母的差是多少
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">48 * (5/8)</gadget>
<output>30</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">48 * (3/8)</gadget>
<output>18</output>

<gadget id="calculator">30 - 18</gadget>
<output>12</output>

<result>12</result>