The number A is 90, the number B is more (1/5) than the number A, and the number A is less than the number B ((())/(())).
甲数是90，乙数比甲数多(1/5)，甲数比乙数少((())/(()))．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(1/5) / (6/5)</gadget>
<output>1/6 = around 0.166667</output>

<result>1/6 = around 0.166667</result>