The playground of the school is 45 meters long and 25 meters wide. After the expansion, the length increases by 17 meters and the width increases by 18 meters. How many square meters does the area increase?
学校的操场长45米，宽25米，扩建后长增加17米，宽增加了18米，面积增加了多少平方米？
<gadget id="calculator">62 * 42</gadget>
<output>2_604</output>

<gadget id="calculator">2_604 - 1_125</gadget>
<output>1_479</output>

<result>1_479</result>