50 kilograms of white sugar, take out (1/5) of it first, and then add (1/5) of it, how many kilograms of white sugar is there at this time
50千克白糖，先取出它的(1/5)后，再增加它的(1/5)，这时白糖有多少千克
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">50 * (4/5) * (6/5)</gadget>
<output>48</output>

<result>48</result>