Process a batch of parts, the ratio of qualified to unqualified is 9:1, what is the qualified rate?
加工一批零件，合格的与不合格的比是9：1，合格率是多少．
<gadget id="calculator">9 + 1</gadget>
<output>10</output>

<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(9/10) * 1</gadget>
<output>9/10 = around 0.9</output>

<result>9/10 = around 0.9</result>