The sum of the numerator and denominator of a fraction is 91. If the numerator is increased by 3 and the denominator is decreased by 3, the resulting fraction is (3/4). What is the original fraction?
一个分数的分子与分母的和是91，如果分子增加3，分母减少3，得到的分数约分后是(3/4)，原来这个分数是多少？
<gadget id="calculator">36 / 56</gadget>
<output>9/14 = around 0.642857</output>

<result>9/14 = around 0.642857</result>