For a fraction, the sum of numerator and denominator is 72, the fraction after reduction is (3/5), what is the original fraction.
一个分数，分子、分母的和是72，约分后的分数是(3/5)，原分数是多少．
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

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

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

<gadget id="calculator">72 * (5/8)</gadget>
<output>45</output>

<gadget id="calculator">(3/8) / 45</gadget>
<output>1/120 = around 0.008333</output>

<gadget id="calculator">72 * (1/120)</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>