A swimming pool is 50 meters long. If the length is reduced by 10 meters and the area is reduced by 300 square meters, what is the area of the swimming pool in square meters?
游泳池长50米，如果长减少10米，面积减少300平方米，那么游泳池的面积是多少平方米．
<gadget id="calculator">300 / 10</gadget>
<output>30</output>

<gadget id="calculator">50 * 30</gadget>
<output>1_500</output>

<result>1_500</result>