The original price of a pair of sports shoes is 120 yuan, and now they are sold at a 20% discount. How much is each pair of sports shoes cheaper than the original price?
一种运动鞋原价每双120元，现在以八折出售，每双运动鞋比原价便宜了多少钱？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">120 * (1/5)</gadget>
<output>24</output>

<result>24</result>