The scale of a design drawing is (1/400), and a rectangular hall in the drawing is 6 cm long and 4.5 cm wide. What is the actual area of this hall in square meters?
一张设计图的比例尺是(1/400)，图中的一个长方形大厅长6厘米，宽4.5厘米．这个大厅的实际面积是多少平方米？
<gadget id="calculator">1 / 400</gadget>
<output>1/400 = around 0.0025</output>

<gadget id="calculator">6 / (1/400) / 100</gadget>
<output>24</output>

<gadget id="calculator">4.5 / (1/400) / 100</gadget>
<output>18</output>

<gadget id="calculator">24 * 18</gadget>
<output>432</output>

<result>432</result>