A pile of coal has 3.6 tons left after its (2/5) is used up, how many tons are left when its (5/8) is used up?
一堆煤用去它的(2/5)后还剩3.6吨，到用去它的(5/8)时，还剩下多少吨？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">3.6 / (3/5)</gadget>
<output>6</output>

<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 - (5/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">6 * (3/8)</gadget>
<output>9/4 = around 2.25</output>

<result>9/4 = around 2.25</result>