Fang Fang drinks (2/5) of a glass of milk, how much is left in this glass of milk.
一杯牛奶，方方喝了它的(2/5)，这杯牛奶还剩下多少．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>