The 20% discount for a pair of shoes is 180 yuan. What is the original price of this pair of shoes?
一双鞋8折是180元，这双鞋原价是多少．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">180 / (4/5)</gadget>
<output>225</output>

<result>225</result>