A commodity priced at 100 yuan is first raised by 10% and then lowered by 10%. What is the current price?
一件100元的商品，先提价10%，再降价10%，现价是多少钱？
<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 + (1/10)</gadget>
<output>11/10 = around 1.1</output>

<gadget id="calculator">1 - (1/10)</gadget>
<output>9/10 = around 0.9</output>

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

<result>99</result>