Baltic_ACM_ICPC_K

// Baltic ACM ICPC K
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
    double n, g, sum, ats;
    cin >> n;
    for(int i=0;i<n;i++)
    {
        cin >> g;
        sum+=g;
    }
    ats=sum/n;
    cout << fixed << setprecision(12) << ats << endl;
    return 0;
}