There is a fraction, if adding its three fractional units is 1, and if subtracting one of its fractional units is (1/2), then what is the fraction
有一个分数，若加上它的三个分数单位后是1，若减去它的一个分数单位后为(1/2)，则这个分数为多少
<gadget id="calculator">8 / 1</gadget>
<output>8</output>

<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<result>5/8 = around 0.625</result>