Jiaojiao has 500 yuan in lucky money, and Qiqi's lucky money is less than Jiaojiao's (1/10), how much lucky money does Qiqi have.
娇娇有500元压岁钱，琪琪的压岁钱数比娇娇少(1/10)，琪琪有多少元压岁钱．
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

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

<gadget id="calculator">500 * (9/10)</gadget>
<output>450</output>

<result>450</result>