A fraction, if one of its fractional units is added, the sum is 1, and if one of its fractional units is subtracted, the difference is (7/8), what is the fraction.
一个分数，若加上它的一个分数单位，和是1，若减去它的一个分数单位，差是(7/8)，这个分数是多少．
<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

<gadget id="calculator">1 - (7/8)</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/8) / 2</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">1 - (1/16)</gadget>
<output>15/16 = around 0.9375</output>

<result>15/16 = around 0.9375</result>