(2/5) tons = how many kilograms.
(2/5)吨=多少千克．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) * 1_000</gadget>
<output>400</output>

<result>400</result>