The current price of a product is 40 yuan, which is 10 yuan lower than the original price, and how much is it lower than the original price
某商品现在售价40元，比原来降低10元，比原价降低了多少
<gadget id="calculator">40 + 10</gadget>
<output>50</output>

<gadget id="calculator">10 / 50</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>