#include <bits/stdc++.h>
using namespace std;

long long k,i,n,v[500005],a[500005],j,mn,mx=-30001,ip,ij,x,u,i1;
ifstream fin("secv3.in");
ofstream fout("secv3.out");
int max(int a,int b){
    if(a>=b) return a;
    return b;
}
float sum,sum1,z,ans=-1000001;
int main()
{
    fin>>n>>i1>>u;
    for(i=1;i<=n;i++) fin>>v[i];
    for(i=1;i<=n;i++) fin>>a[i];
    for (int i = 1; i <= n; i++) {
    int sum = 0;sum1=0;
    for (int j = i; j <= n; j++) {
        sum += v[j];
        sum1+=a[j];
        z=sum/sum1;
        x=j-i+1;
        if(x>=i1&&x<=u&&z>ans) {ans=z;}
    }
}

fout<<fixed<<setprecision(2)<<ans;
    return 0;
}