#include <stdio.h>
#include <math.h>

int c[30000];
int t[30000];

int main()
{
    FILE *in=fopen("secv3.in","r");
    FILE *out=fopen("secv3.out","w");
    int n,i,j,k,l,u;
    float mr=-1;
    fscanf(in,"%d%d%d",&n,&l,&u);
    for(i=0;i<n;i++){
        fscanf(in,"%d",&c[i]);
    }
    for(i=0;i<n;i++){
        fscanf(in,"%d",&t[i]);
    }
    for(i=0;i<n;i++){
        for(j=i;j<n;j++){
            if(i-j+1<l || i-j+1>u) continue;
            float ct=0,tt=0;
            for(k=i;k<=j;k++){
                ct+=c[k];
                tt+=t[k];
            }
            float r=ct/tt;
            if(r>mr) mr=r;
        }
    }
    fprintf(out,"%f",round(mr*100)/100);
    return 0;
}