The price of a commodity is reduced by 10% for the first time, and the price is reduced by 20% for the second time. How much is the price of this commodity lower than the original price?
一种商品，第一次降价10%，第二次又降价20%，现在这种商品的价格比原价降低了多少
<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">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 * (9/10) * (4/5)</gadget>
<output>18/25 = around 0.72</output>

<gadget id="calculator">1 - (18/25)</gadget>
<output>7/25 = around 0.28</output>

<gadget id="calculator">(7/25) / 1</gadget>
<output>7/25 = around 0.28</output>

<result>7/25 = around 0.28</result>