For a simple fraction, the sum of the numerator and the denominator is 40. Subtract 3 from both the numerator and the denominator to obtain (5/12). Find this fraction.
一个最简分数，分子、分母的和是40，分子、分母都减去3，约分后得(5/12)，求这个分数．
<gadget id="calculator">40 - 3 - 3</gadget>
<output>34</output>

<gadget id="calculator">5 + 12</gadget>
<output>17</output>

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

<gadget id="calculator">34 * (5/17)</gadget>
<output>10</output>

<gadget id="calculator">10 + 3</gadget>
<output>13</output>

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

<gadget id="calculator">34 * (12/17)</gadget>
<output>24</output>

<gadget id="calculator">24 + 3</gadget>
<output>27</output>

<gadget id="calculator">13 / 27</gadget>
<output>13/27 = around 0.481481</output>

<result>13/27 = around 0.481481</result>