fraction after simplification is (5/12), the sum of the numerator and denominator of the original fraction is 85, what is the original fraction.
一个分数化简后是(5/12)，原分数的分子和分母的和是85，原分数是多少．
<gadget id="calculator">12 + 5</gadget>
<output>17</output>

<gadget id="calculator">5 / 17</gadget>
<output>5/17 = around 0.294118</output>

<gadget id="calculator">12 / 17</gadget>
<output>12/17 = around 0.705882</output>

<gadget id="calculator">85 * (12/17)</gadget>
<output>60</output>

<gadget id="calculator">(5/17) / 60</gadget>
<output>1/204 = around 0.004902</output>

<gadget id="calculator">85 * (1/204)</gadget>
<output>5/12 = around 0.416667</output>

<result>5/12 = around 0.416667</result>