A is B's (7/8), that is, how much A is less than B.
甲是乙的(7/8)，就是甲比乙少多少．
<gadget id="calculator">8 - 7</gadget>
<output>1</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<result>1/8 = around 0.125</result>