#include<cstdio>
#include<fstream>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<vector>
#include<bitset>
#include<deque>
#include<queue>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<unordered_map>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<ll,ll>

using namespace std;

const int nmax = 30005;

int n, L, U, i, c[nmax], t[nmax];
double l, r, m, sol, s[nmax];

deque<int> q;

bool check(double x)
{
    for(int i = 1; i <= n; i++)
    {
        double y = 1.0 * c[i] - x * t[i];
        s[i] = s[i - 1] + y;
    }

    q.clear();

    for(int i = L; i <= n; i++)
    {
        while(!q.empty() && s[i - L] <= s[q.back()])
            q.pop_back();

        q.pb(i - L);

        if(q.front() == i - U - 1)
            q.pop_front();

        if(s[i] - s[q.front()] >= 0)
            return 1;
    }

    return 0;
}

int main()
{
    freopen("secv3.in", "r", stdin);
    freopen("secv3.out", "w", stdout);

    scanf("%d%d%d", &n, &L, &U);

    for(i = 1; i <= n; i++)
        scanf("%d", &c[i]);

    for(i = 1; i <= n; i++)
        scanf("%d", &t[i]);

    l = 0.0;
    r = 1000.0;
    for(i = 1; i <= 100; i++)
    {
        m = (l + r) / 2;
        if(check(m))
        {
            sol = m;
            l = m;
        }
        else r = m;
    }

    cout << fixed << setprecision(2) << sol;

    return 0;
}