The price of a kind of electric fan has been reduced twice, the first time the price has been reduced by 20%, and the second time the price has been reduced by 10%. What is the current price?
一种电扇先后两次降价，第一次降价20%，第二次降价10%，现在的价钱是原来的多少．
<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">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</gadget>
<output>9/10 = around 0.9</output>

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

<result>18/25 = around 0.72</result>