There are fewer boys than girls in the sixth grade (1/5), and how many boys are girls
六年级男生比女生少(1/5)，男生是女生的多少
<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>

<result>4/5 = around 0.8</result>