There are 7 round tables and 6 square tables in the pastoral restaurant. A round table can seat 3 people, and a square table can seat 4 people. How many guests can be received at the same time?
田园餐厅有圆桌7张，方桌6张，一张圆桌坐3人，一张方桌坐4人．可同时接待多少位客人？
<gadget id="calculator">3 * 7</gadget>
<output>21</output>

<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<gadget id="calculator">21 + 24</gadget>
<output>45</output>

<result>45</result>