There are 12 tons of steel in the warehouse, (1/5) of the total is used for the first time, and 3 tons are used for the second time, how many tons are left?
仓库里有12吨钢材，第一次用去总数的(1/5)，第二次用去3吨，还剩下多少吨．
<gadget id="calculator">1 / 5</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">12 * (4/5)</gadget>
<output>48/5 = around 9.6</output>

<gadget id="calculator">(48/5) - 3</gadget>
<output>33/5 = around 6.6</output>

<result>33/5 = around 6.6</result>