The cost of a product has dropped by 18%, what is the cost now.
一种产品成本下降了18%，现在成本是原来的多少．
<gadget id="calculator">18 / 100</gadget>
<output>9/50 = around 0.18</output>

<gadget id="calculator">1 - (9/50)</gadget>
<output>41/50 = around 0.82</output>

<result>41/50 = around 0.82</result>