If (1/9) of the number of people in class A is transferred to class B, the number of people in the two classes will be equal. It is known that there is a person in class B, and how many people are in class A.
把甲班人数的(1/9)调入乙班，则两班人数相等，已知乙班有a人，甲班有多少人．
<gadget id="calculator">9 / 7</gadget>
<output>9/7 = around 1.285714</output>

<result>9/7 = around 1.285714</result>