#include<bits/stdc++.h> using namespace std; int n,k; double lst[200005]; bool check(double x){ int sum=0; for(int i = 1;i <= n;i++) sum += (lst[i] / x); if(sum >= k) return true; else return false; } int main(){ cin >> n >> k; double l = 0,r= -1,ans = 0; for(int i=1;i<=n;i++){ cin>>lst[i]; r=max(r,lst[i]); } int L=0,R=r*100; while(L<=R){ int mid=L+(R-L)/2; if(check((double)mid/100)){ ans=mid; L=mid+1; } else{ R=mid-1; } } ans/=100; if(ans<0.01){ cout<<0.00; } else{ cout<<fixed<<setprecision(2)<<ans<<endl; } }