#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,age[100];
    double all,avge;
    cin >> n;
    for(int i=0;i<n;i++){
        cin >> age[i];
        all=all+age[i];
    }
    avge=all/n;
    cout << avge;
    return 0;
}