A product is processed and sold, and the price is 990 yuan after a 10% price reduction. How much is the price reduction of this product?
一种商品进行处理销售，降价10%后售价是990元，该商品降价多少元？
<gadget id="calculator">10 / 100</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">990 / (9/10)</gadget>
<output>1_100</output>

<gadget id="calculator">1_100 * (1/10)</gadget>
<output>110</output>

<result>110</result>