After the price of a pair of sports shoes is reduced by 20%, 40 yuan is saved. What is the original price?
一双运动鞋降价20%后，节约了40元，原价是多少．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">40 / (1/5)</gadget>
<output>200</output>

<result>200</result>