The numerator of a fraction is 19 smaller than the denominator. After adding 5 to the numerator, it can be reduced to (5/7). What is the original fraction?
一个分数的分子比分母小19，把它的分子加5后可以约简为(5/7)，原来的分数是多少．
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(5/7) * 19</gadget>
<output>95/7 = around 13.571429</output>

<gadget id="calculator">(95/7) - 5</gadget>
<output>60/7 = around 8.571429</output>

<gadget id="calculator">1 - (5/7)</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">(60/7) / (2/7)</gadget>
<output>30</output>

<gadget id="calculator">30 + 19</gadget>
<output>49</output>

<gadget id="calculator">(60/7) / (2/7) / 49</gadget>
<output>30/49 = around 0.612245</output>

<result>30/49 = around 0.612245</result>