The price of a product is reduced by 30% during the promotion period, and then increased by 30% after the promotion, what is the price of the product at this time?
某商品在促销时期降价30%，促销过后又涨30%，这时商品的价格是原来价格的多少
<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">(13/10) / 1</gadget>
<output>13/10 = around 1.3</output>

<gadget id="calculator">1 * (7/10) * (13/10)</gadget>
<output>91/100 = around 0.91</output>

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