#include<stdio.h>
int main()
{int v[30001],x[30001],i,j,u,L,p,st,sc,n;
float max=0,raport;
FILE *f=fopen("secv3.in","r");
FILE *g=fopen("secv3.out","w");
fscanf(f,"%d %d %d",&n,&L,&u);
for (i=1;i<=n;i++) fscanf(f,"%d",&v[i]);
for (i=1;i<=n;i++) fscanf(f,"%d",&x[i]);
for (i=1;i<=n;i++)
	{p=L;
	while (p<=u&&i+p<=n)
		{
		st=0; sc=0;
		for (j=i;j<i+p;j++)
		       {	sc+=v[i]; st+=x[i];}
		raport=(float)sc/st;
		if (raport>max) max=raport;
		p++;}
	}
fprintf(g,"%.2f",max);
fclose(f);
fclose(g);
return 0;}