A bag of white sugar has 40 kilograms, how much is left after using (2/8).
一袋白糖有40千克，用了(2/8)还剩多少．
<gadget id="calculator">2 / 8</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">40 * (1/4)</gadget>
<output>10</output>

<gadget id="calculator">40 - 10</gadget>
<output>30</output>

<result>30</result>