Red Sun Plaza originally had a rectangular flower garden. If the width is increased by 20 meters during expansion, the area will increase by 400 square meters. If the length is reduced by 15 meters, the area will be reduced by 120 square meters. How many square meters was the original area of the flower garden?
红太阳广场原有一个长方形花圃，扩建时如果把宽增加了20米，面积增加了400平方米．如果长缩小了15米，面积就减少120平方米，问这个花圃原占地面积是多少平方米？
<gadget id="calculator">400 / 20</gadget>
<output>20</output>

<gadget id="calculator">120 / 15</gadget>
<output>8</output>

<gadget id="calculator">20 * 8</gadget>
<output>160</output>

<result>160</result>