Nini uses rectangular paper with a length of 20cm and a width of 10cm to form the largest cylinder. Xuehong uses rectangular paper with a length of 30cm and width to form the largest cylinder. The volume of Xuehong is the cylinder surrounded by Nini. How many times the volume of the body?
妮妮用长20cm，宽10cm的长方形纸围成容积最大的圆柱体，雪红用长30cm，宽20cm的长方形纸围成容积最大的圆柱体，雪红围的体积是妮妮围成的圆柱体的体积的多少倍？
<result>4.5</result>