(1/5) of the students in Group A are transferred to Group B, and the number of the two groups is equal. How much is Group B less than Group A?
甲组学生的(1/5)调入乙组，两组人数相等，原来乙组比甲组少多少
<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>