The unit price of a piece of clothing is 100 yuan. First reduce it by 10%, and then increase the price by 10%. What is the current price?
一件衣服单价100元，先降低10%，再提价10%，现在是多少元．
<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">1 + (1/10)</gadget>
<output>11/10 = around 1.1</output>

<gadget id="calculator">100 * (9/10) * (11/10)</gadget>
<output>99</output>

<result>99</result>