pile of 2.4 tons of coal, 20% of the total is transported on the first day, and - tons on the second day, how many tons is this pile of coal less than the original?
一堆煤2.4吨，第一天运走总数的20%，第二天运走-吨，这时这堆煤比原来少多少吨？
<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">2.4 * (4/5)</gadget>
<output>1.92</output>

<gadget id="calculator">1.92 - 1</gadget>
<output>0.92</output>

<result>0.92</result>