The current price of a pair of trousers is 50 yuan, which is 20% lower than the original price. How much is the original price?
一条裤子现在售价50元，比原来降价20%，原来售价多少元．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">50 / (4/5)</gadget>
<output>125/2 = around 62.5</output>

<result>125/2 = around 62.5</result>