The cafeteria brings (2/5) tons of coal, and after using up part of it, there is still (1/5) of the total amount left. How many tons are left?
食堂运来(2/5)吨煤，用去一部分后还剩下总量的(1/5)，还剩下多少吨．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(2/5) * (1/5)</gadget>
<output>2/25 = around 0.08</output>

<result>2/25 = around 0.08</result>