#include <stdio.h>
#define nmax 30001

int n,u,l;
long C[nmax],T[nmax],C2[nmax],T2[nmax];
void read()
 {
 int i;
 FILE *f=fopen("secv3.in","r");
 fscanf(f,"%d %d %d",&n,&l,&u);
 for(i=1;i<=n;i++)
  fscanf(f,"%ld",&C[i]);
 for(i=1;i<=n;++i)
  fscanf(f,"%ld",&T[i]);
 for(i=1;i<=n;++i)
  {
  T2[i]=T2[i-1]+T[i];
  C2[i]=C2[i-1]+C[i];
  }
 }
void solve()
 {
 FILE *g=fopen("secv3.out","w");
 float sc,st,x,y;
 int j,i;
 st=sc=-1;
 for(j=l;j<=u;++j)
  for(i=j;i<=n;++i)
   {
   x=C2[i]-C2[i-l-(j-l)];
   y=T2[i]-T2[i-l-(j-l)];
   if(sc==-1||x*st>y*sc)
    {
    sc=x;
	st=y;
    }
   }
 fprintf(g,"%.2f",(sc/st));
 }
int main()
 {
 read();
 solve();
 return 0;
 }