There are 38 seats in the first row of a certain theater, each subsequent row has 2 more seats than the previous row, and the last row has 76 seats. How many seats are there in total in this theater?
某剧场第一排有38个座位，往后每一排都比前一排多2个座位，最后一排有76个座位，这个剧场一共有多少个座位？
<gadget id="calculator">38 + 76</gadget>
<output>114</output>

<gadget id="calculator">76 - 38</gadget>
<output>38</output>

<gadget id="calculator">38 / 2</gadget>
<output>19</output>

<gadget id="calculator">19 + 1</gadget>
<output>20</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">114 * 10</gadget>
<output>1_140</output>

<result>1_140</result>