A rope, cut off 20% of the total length for the first time, cut off the remaining 25% for the second time, and how much of the total length is cut off for the second time.
一根绳子，第一次剪去总长的20%，第二次剪去余下的25%，第二次剪去总长的多少．
<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">25 / 100</gadget>
<output>1/4 = around 0.25</output>

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

<result>1/5 = around 0.2</result>