For a fraction, if 1 is added to the numerator, it becomes 1, and 1 is subtracted from the numerator to obtain (3/4). What is the original fraction?
一个分数，如果分子加上1就是1，分子减去1就是(3/4)，原来这个分数是多少．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 + (3/4)</gadget>
<output>7/4 = around 1.75</output>

<gadget id="calculator">(7/4) / 2</gadget>
<output>7/8 = around 0.875</output>

<result>7/8 = around 0.875</result>