//https://infoarena.ro/problema/secv3
//#pragma GCC optimize ("Ofast")
//#pragma GCC optimize ("fast-math")
//#pragma GCC optimize ("unroll-loops")
//#define _USE_MATH_DEFINES
#include <iostream>
#include <fstream>
#include <vector>
//#include <cstring>
//#include <cmath>
//#include <bitset>
//#include <queue>
//#include <utility>
//#include <algorithm>
//#include <string>
//#include <map>
//#include <climits>
#include <iomanip>
using namespace std;

ifstream fin("secv3.in");
ofstream fout("secv3.out");

float c[30005], t[30005];
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int n, l, u, i, j;
	float maxi = 0;
	float sumc = 0, sumt = 0;
	
	fin >> n >> l >> u;
	for (i = 1; i <= n; ++i)
	{
		fin >> c[i];
		c[i] += c[i - 1];
	}
	for (i = 1; i <= n; ++i)
	{
		fin >> t[i];
		t[i] += t[i - 1];
	}

	j = 1;
	for (i = l; i <= n; ++i)
	{
		if (j <= i - u)
			j = i - u;

		maxi = max(maxi, ((c[i] - c[j - 1]) / (t[i] - t[j - 1])));
		maxi = max(maxi, ((c[i] - c[i - l]) / (t[i] - t[i - l])));
	}

	fout << fixed << setprecision(2) << maxi;

	return 0;
}