The toy factory has produced 450 cars, and the passing rate is 90%. How many unqualified products are there?
玩具厂生产了450辆小汽车，合格率是90%，不合格的产品有多少辆．
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">450 * (1/10)</gadget>
<output>45</output>

<result>45</result>