After transferring (1/7) people from class 51 to class 52, the number of people in the two classes is equal, and the original number of people in class 52 is that of class 51 ((())/(())).
把五一班的人调出(1/7)到五二班后，两班人数相等，原来五二班人数是五一班的((())/(()))．
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">(1/7) * 2</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/7)</gadget>
<output>5/7 = around 0.714286</output>

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