20 increase its (1/5), and then decrease (1/5), what is the result
20增加它的(1/5)，再减少(1/5)后，结果是多少
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

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

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

<gadget id="calculator">20 * (6/5) * (4/5)</gadget>
<output>96/5 = around 19.2</output>

<result>96/5 = around 19.2</result>