There is a fraction, if 4 is added to the denominator, the numerator remains unchanged, and after division is (1/6); if 4 is added to the numerator, the denominator remains unchanged, and after division, it is (1/4), then what is the original fraction ．
有一个分数，如果分母加上4，分子不变，约分后是(1/6)；如果分子加上4，分母不变，约分后是(1/4)，那么，原分数是多少．
<gadget id="calculator">6 * 10</gadget>
<output>60</output>

<gadget id="calculator">60 - 4</gadget>
<output>56</output>

<gadget id="calculator">10 / 56</gadget>
<output>5/28 = around 0.178571</output>

<result>5/28 = around 0.178571</result>