There are more boys than girls (1/8), how much less girls than boys
男生比女生多(1/8)，女生比男生少多少
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/8) - 1</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 + (1/8)</gadget>
<output>9/8 = around 1.125</output>

<gadget id="calculator">(1/8) / (9/8)</gadget>
<output>1/9 = around 0.111111</output>

<result>1/9 = around 0.111111</result>