A rectangular swimming pool is 25 meters long. After expansion, the length increases by 5 meters and the area increases by 75 square meters. How many square meters does this swimming pool occupy now?
一个长方形游泳池，长25米，扩建后长增加了5米，面积增加了75平方米，现在这个游泳池占地多少平方米？
<gadget id="calculator">25 + 5</gadget>
<output>30</output>

<gadget id="calculator">75 / 5</gadget>
<output>15</output>

<gadget id="calculator">30 * 15</gadget>
<output>450</output>

<result>450</result>