A certain product has a promotional activity, the price is reduced (9/100), and on this basis, it is returned (5/100). What percentage of the original price is the product price at this time?
某商品进行促销活动，降价(9/100)，在此基础上又返回(5/100)，此时的商品价格相当于原价的百分之几？
<gadget id="calculator">9 / 100</gadget>
<output>9/100 = around 0.09</output>

<gadget id="calculator">1 - (9/100)</gadget>
<output>91/100 = around 0.91</output>

<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 - (1/20)</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">(91/100) * (19/20)</gadget>
<output>1_729/2_000 = around 0.8645</output>

<result>1_729/2_000 = around 0.8645</result>