#include<cstdio>
using namespace std;
int suma(int v[],int p,int u)
{if(p==u) return v[p];
return suma (v,p,(p+u)/2)+suma(v,(p+u)/2+1,u);
}
int main()
{int n,l,u,i,j,a[100],b[100];
float max=-32000;
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,"%d",&a[i]);
for(i=1;i<=n;i++)
fscanf(f,"%d",&b[i]);
if(suma(a,n,n)/suma(b,n,n)>max)
max=(float)suma(a,n,n)/suma(b,n,n);
for(i=1;i<=n-u+1;i++)
for(j=i+l-1;j<=i+u-1;j++)
if(suma(b,i,j)&&suma(a,i,j)/suma(b,i,j)>max)
max=(float)suma(a,i,j)/suma(b,i,j);
fprintf(g,"%.2f",max);
return 0;
}