The school playground used to be 30 meters long and 20 meters wide. Later, it was expanded. The length of the playground increased by 10 meters and the width increased by 8 meters. How many square meters has the playground area increased now?
学校的操场原来长30米，宽20米，后来进行扩建，操场的长增加了10米，宽增加了8米，现在操场的面积增加了多少平方米？
<gadget id="calculator">30 + 10</gadget>
<output>40</output>

<gadget id="calculator">20 + 8</gadget>
<output>28</output>

<gadget id="calculator">40 * 28</gadget>
<output>1_120</output>

<gadget id="calculator">30 * 20</gadget>
<output>600</output>

<gadget id="calculator">1_120 - 600</gadget>
<output>520</output>

<result>520</result>