#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;

int main(){

	int l,u,n;
	int v1[30000];
	int v2[30000]; 
	ifstream f("secv3.in");
	ofstream g("secv3.out");
	f >> n >> l >> u;
	for (int i = 0; i < n; i++){
		f >> v1[i];	
	} 	
	
	for (int i = 0; i < n; i++){
		f >> v2[i];
	} 
	
	double gMax = 0;
	double gTemp;
	int s1Temp;
	int s2Temp; 
	int lTemp = 1;
	int j;
	for(int i = 0; i< n ; i++){
		gTemp = (double)v1[i]/v2[i];
		s1Temp = v1[i];
		s2Temp = v2[i];
		lTemp = 1;
		j = i;
		while(j < n){
			if(lTemp <= u){
				if(lTemp >= l){
					if(gMax < gTemp)
						gMax = gTemp;
				}			
			}
			else break;
			if(j+1 < n){
				j++;
				lTemp ++;
				s1Temp += v1[j];
				s2Temp += v2[j];
				gTemp = (double)s1Temp/s2Temp;			
			}else break;
		} 
	}
	g << std::setprecision(2) << gMax;
	//delete [] v1;
	//delete [] v2;
	g.close();
	f.close();
	return 0;
}