There are 28 rows of seats in a certain theater, each row at the back has 2 more seats than the row in front, and the last row has 108 seats, how many seats are there in total in this theater?
某剧院有28排座位，每后面一排都比前面一排多2个座位，最后一排有108个座位，这个剧院共有多少个座位．
<gadget id="calculator">28 - 1</gadget>
<output>27</output>

<gadget id="calculator">27 * 2</gadget>
<output>54</output>

<gadget id="calculator">108 - 54</gadget>
<output>54</output>

<gadget id="calculator">54 + 108</gadget>
<output>162</output>

<gadget id="calculator">28 / 2</gadget>
<output>14</output>

<gadget id="calculator">162 * 14</gadget>
<output>2_268</output>

<result>2_268</result>