After being transferred from class A (1/7) to class B, the number of people in the two classes is equal, and the original number of people in class B is that of class A ((())/(())).
从甲班调(1/7)到乙班后，两班的人数就相等，原来乙班人数是甲班的((())/(()))．
<gadget id="calculator">7 - 1 - 1</gadget>
<output>5</output>

<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<result>5/7 = around 0.714286</result>