#include <stdio.h>
#include <string.h>
#define nmax 30001
unsigned int n,l,u,c[nmax],t[nmax],i,j,k,max;
char text[nmax*5];
 
int main(){
 freopen("secv3.in","r",stdin);
 freopen("secv3.out","w",stdout);
 
 scanf("%d %d %d\n",&n,&l,&u);

 gets(text);
 j = strlen(text);
 for(i=0,k=1;i<j;++i)
    if(text[i] == ' ')
        c[k] += c[k-1],
        k++;
    else
        c[k] = c[k] * 10 + text[i] - '0';
 c[k] += c[k-1];
 
 gets(text);
 j = strlen(text);
 for(i=0,k=1;i<j;++i)
    if(text[i] == ' ')
        t[k] += t[k-1],
        k++;
    else
        t[k] = t[k] * 10 + text[i] - '0';
 t[k] += t[k-1];
 
 for(i=l;i<=u;++i)
    for(j=i;j<=n;++j)
        if( ((c[j]-c[j-i])*100) / (t[j]-t[j-i]) > max )
            max = ((c[j]-c[j-i])*100) / (t[j]-t[j-i]);
            
 printf("%d.%02d",max/100,max%100);
 
 return 0;
}