A suit is 180 yuan, and the price of trousers is 1/5 cheaper than the suit. How much is the price of a pair of trousers?
一件西服180元，裤子的价格比西服便宜(1/5)，一裤子的价格是多少元？
<gadget id="calculator">1 / 5</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">180 * (4/5)</gadget>
<output>144</output>

<result>144</result>