The school playground used to be 80 meters long and 30 meters wide, but the length increased by 20 meters and the width doubled. After the expansion, how many square meters has the playground increased?
学校操场原来长80米，宽30米，长增加了20米，宽是原来的2倍，扩建后，操场比原来增加了多少平方米？
<gadget id="calculator">80 + 20</gadget>
<output>100</output>

<gadget id="calculator">30 * 2</gadget>
<output>60</output>

<gadget id="calculator">100 * 60</gadget>
<output>6_000</output>

<gadget id="calculator">80 * 30</gadget>
<output>2_400</output>

<gadget id="calculator">6_000 - 2_400</gadget>
<output>3_600</output>

<result>3_600</result>