#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int mod = 1e9 + 7;
const int inf = (1 << 30) - 1;
const ll infll = (1LL << 61) - 1;

double N;

int main()
{
    cin >> N;
    vector<double> a((int)N);
    double s = 0;
    for (int i = 0; i < N; i++)
    {
        cin >> a[i];
        s += a[i];
    }
    cout << s / N << endl;
}