After a 40% discount on a product, the selling price is 18 yuan. If it is sold at the original price, how much more can it be sold for?
一件商品打六折后，售价是18元．如果按原价卖出，可以多卖多少元．
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">18 / (3/5)</gadget>
<output>30</output>

<gadget id="calculator">30 - 18</gadget>
<output>12</output>

<result>12</result>