fraction in the simplest form, if 1 is added to the numerator, it can be reduced to (2/3), and if 1 is subtracted from the numerator, it can be reduced to (1/2). What is this score.
一个最简分数，若分子加上1，可以约简为(2/3)，若分子减去1，可化简成(1/2)．这个分数是多少．
<gadget id="calculator">7 / 12</gadget>
<output>7/12 = around 0.583333</output>

<result>7/12 = around 0.583333</result>