There were originally 9 rows of seats in the lecture theater, with 20 chairs in each row. During a meeting, 48 chairs were temporarily added. How many chairs are there in this lecture theater?
阶梯教室里原来有9排座位，每排20张椅子．有一次开会时，临时又增加了48张椅子，这进阶梯教室里一共有多少张椅子？
<gadget id="calculator">20 * 9</gadget>
<output>180</output>

<gadget id="calculator">180 + 48</gadget>
<output>228</output>

<result>228</result>