How much is 100 increased by 20 and then decreased by 20%.
100增加20然后再减少20%是多少．
<gadget id="calculator">100 + 20</gadget>
<output>120</output>

<gadget id="calculator">20 / 100</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">120 * (4/5)</gadget>
<output>96</output>

<result>96</result>