For a kind of computer software, the price of the second quarter is 10% lower than that of the first quarter, and the price of the third quarter is 10% lower than that of the second quarter. What is the total price reduction in the two quarters?
一种电脑软件，第二季度比第一季度降价10%，第三季度比第二季度降价10%．两个季度一共降价百分之几？
<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">(9/100) + (1/10)</gadget>
<output>19/100 = around 0.19</output>

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