#include<stdio.h>


int main()
{
 FILE *f=fopen("secv3.in", "r");
 unsigned int n, l, u, cost[30002], timp[30002], i, j, k;
 float rap, max, MAX;
 long c, t;

 fscanf(f, "%d%d%d", &n, &l, &u);
 for(i=1; i<=n; i++)
   fscanf(f, "%d", &cost[i]);
 for(i=1; i<=n; i++)
   fscanf(f, "%d", &timp[i]);
 fclose(f);

 cost[0]=timp[0]=0;
 max=0;
 MAX=0;
 for(i=l; i<=n; i++)
  {
   c=0;
   t=0;
   for(j=i; j>=i-l+1; j--)
    {
     c=c+cost[j];
     t=t+timp[j];
    }
   rap=(float)c/t;
   max=rap;
   for(k=j; k>=i-u+1 && k>=1; k--)
    {
     c=c+cost[k];
     t=t+timp[k];
     rap=(float)c/t;
     if(rap>max)
       max=rap;
    }
   if(max>MAX)
     MAX=max;
  }

 f=fopen("secv3.out", "w");
 fprintf(f, "%.2f", MAX);
 fclose(f);

 return 0;

}