A batch of parts, 10 qualified, 1 unqualified, how many unqualified ones account for the total.
一批零件，10个合格，1个不合格，不合格的占总数的多少．
<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<gadget id="calculator">1 / 11</gadget>
<output>1/11 = around 0.090909</output>

<result>1/11 = around 0.090909</result>