include <bits/stdc++.h>

//ccccccccccccccccccccccccccccccccccccccccc //+++++++++++++++++++++++++++++++++++++++++ //+++++++++++++++++++++++++++++++++++++++++ using namespace std; double n,k,sum; int main(){ cin>>n; for(int i = 1;i<=n;i++){ cin>>k; sum+=k; } printf("%.2lf\n",sum/n); return 0; }