There are 6 kilograms of oil, used up (2/3), how many kilograms of oil are left.
有6千克油，用去了(2/3)，还剩下多少千克油．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">6 * (1/3)</gadget>
<output>2</output>

<result>2</result>