For a computer, first reduce the price by 30%, and then increase the price by 30%, what is the current price of the original price?
一台电脑，先降价30%，又提价三成，现价是原价的多少
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 + (3/10)</gadget>
<output>13/10 = around 1.3</output>

<gadget id="calculator">(7/10) * (13/10)</gadget>
<output>91/100 = around 0.91</output>

<result>91/100 = around 0.91</result>