A bundle of rope is 125 meters long, 40% of it is used up for the first time, and (2/5) is used up for the second time. By what percentage is the rope shorter after using it twice?
一捆绳子长125米，第一次用去它的40%，第二次用去它的(2/5)．用了两次后，这根绳子短百分之几？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) + (2/5)</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>