#include<stdio.h>
int n,l,u,i,p;
double cit,c[30001],t[30001],sc,sol;
int main()
{
	FILE *f,*g;
	f=fopen("secv3.in","r");
	g=fopen("secv3.out","w");
	fscanf(f,"%d%d%d",&n,&l,&u);
	for(i=1;i<=n;i++)
	{ fscanf(f,"%lf",&cit);c[i]=c[i-1]+cit;}
	for(i=1;i<=n;i++)
	{ fscanf(f,"%lf",&cit);t[i]=t[i-1]+cit;}
	u=(2*l<u)?2*l:u;
	for(p=l;p<=u;p++)
	{
		for(i=0;i<=n-p;i++)
		{ sc=(c[i+p]-c[i])/(t[i+p]-t[i]);
		  sol=(sc>sol)?sc:sol;
		}
	}
	fprintf(g,"%.2lf",sol);
	fcloseall();
	return 0;
}