A bucket of water weighs 20 kilograms, if (2/5) of it is used, how many kilograms are used?
一桶水重20千克，用去它的(2/5)，用去多少千克？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 * (2/5)</gadget>
<output>8</output>

<result>8</result>