The price of a commodity is 80 yuan, which is 20 yuan lower than in the past. How much is the reduction.
一种商品售价80元，比过去降低了20元，降低了多少．
<gadget id="calculator">80 + 20</gadget>
<output>100</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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