The number of people in class A is 25% more than that of class B, and the number of people in class B is the number of people in class A.
甲班人数比乙班多25%，乙班人数是甲班的多少．
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

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

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