#include <fstream>
#include <iomanip>

using namespace std;

ifstream f("secv3.in");
ofstream g("secv3.out");

int costul[30002],timpul[30002],n,i,j,l,u,k,x;
float raport,maxim,sumacost,sumatimp;
int main()
{
f>>n>>l>>u;
costul[0]=timpul[0]=0;
for(i=1;i<=n;i++)
{
    f>>x;
      costul[i]=costul[i-1]+x;
}
for(i=1;i<=n;i++)
{
      f>>x;
        timpul[i]=timpul[i-1]+x;
}
k=l;
while(k<u)
{
    for(i=1;i<=n-k+1;i++)
    {
        for(j=n-k+1;j<=n;j++)
        {
            sumacost=costul[j]-costul[i-1];
            sumatimp=timpul[j]-timpul[i-1];
            raport=sumacost/sumatimp;
               if(raport>maxim)
                  maxim=raport;
        }
    }
    k++;
}
g<<fixed<<setprecision(2)<<maxim;

    return 0;
}