For a pile of coal, 0.6 tons are used for the first time, and the rest (3/5) is used for the second time, so there is still 0.8 tons left. How many tons was this pile of coal originally?
一堆煤，第一次用去0.6吨，第二次用去余下的(3/5)，这时还剩下0.8吨．这堆煤原来有多少吨？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">0.6 * (3/5)</gadget>
<output>0.36</output>

<gadget id="calculator">0.8 - 0.36</gadget>
<output>0.44</output>

<gadget id="calculator">0.6 + 0.44</gadget>
<output>1.04</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1.04 / (2/5)</gadget>
<output>2.6</output>

<result>2.6</result>