There are 210 seats on the upper floor of the opera house, which is 518 seats less than the downstairs. How many people can this opera house accommodate?
歌剧院楼上有210个座位，比楼下少518个座位，这个歌剧院共能容纳多少人？
<gadget id="calculator">210 + 518</gadget>
<output>728</output>

<gadget id="calculator">210 + 728</gadget>
<output>938</output>

<result>938</result>