After the price of a product is reduced by 10%, the price is reduced by another 10%. How much is the current price less than the original price?
一件商品降价10%后，又降价10%，现价比原价少多少
<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">(9/10) * (1/10)</gadget>
<output>9/100 = around 0.09</output>

<gadget id="calculator">(1/10) + (9/100)</gadget>
<output>19/100 = around 0.19</output>

<result>19/100 = around 0.19</result>