The number of people in Class Six 1 is transferred out (1/5), which is exactly equal to the number of Class Six 2. The original number of people in Class Six 2 is the number of Class Six 1
把六1班的人调出(1/5)后刚好与六2班人数相等，原来六2班人数是六1班的多少
<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>