#include<bits/stdc++.h>
using namespace std;

int n,m;
double a[100005];

bool check(double v){
	double num=0;
	for(int i=1;i<=n;i++){
		num+=a[i]/v;
	}
	return num>=m;
}

double mmax;
int main(){
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++){
		cin>>a[i];
		mmax=max(mmax,a[i]);
	}
	double l=1,r=mmax,mid;
	while(l<r){
		mid=(l+r+0.01)/2;
		if(check(mid)) l=mid;
		else r=mid-1;
	}
	int c=l;
	cout<<c<<".00"<<endl;;
	return 0;
}