The current price of a drug is 10% lower than the original price, and the current price is the original price.
一种药品的现价比原价降10%，现价是原价的多少．
<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>

<result>9/10 = around 0.9</result>