There are 84 students in Class A and Class B. When 6 students are transferred from Class A to Class B, the number of students in the two classes is exactly equal. So how many students are there in Class A?
甲、乙两班共有84名同学，当从甲班调出6名同学到乙班后，两班的人数恰好相等，那么甲班原来有多少人．
<gadget id="calculator">84 / 2</gadget>
<output>42</output>

<gadget id="calculator">42 + 6</gadget>
<output>48</output>

<result>48</result>