The factory shipped in 12.6 tons of coal, used 5.8 tons, and later shipped in another 15.6 tons. How much coal does the factory have now?
工厂运进12.6吨煤，用去5.8吨，后来又运进15.6吨，现在工厂有多少煤？
<gadget id="calculator">12.6 - 5.8</gadget>
<output>6.8</output>

<gadget id="calculator">6.8 + 15.6</gadget>
<output>22.4</output>

<result>22.4</result>