The current price of a product is 4 yuan, which is 1 yuan lower than the original price, and how much is it lower than the original price
某商品现在售价4元，比原价降低1元，比原价降低了多少
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

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

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