A cylindrical bucket with a height of 8 decimeters is half filled with water. After pouring out 12 liters of water, the remaining water occupies exactly 20% of the volume of the bucket. What is the area of the bottom of this bucket in square decimeters?
一个高为8分米的圆柱形水桶里，装了半桶水．把水倒出12升后，剩下的水恰好占水桶容积的20%．这个水桶的底面积是多少平方分米？
<result>0.4</result>