#include <bits/stdc++.h>
using namespace std;
int main() {
  double orange, total, n;
  cin >> n;
  total = n * 100.000000000000;
  for (int i = 0; i < n; i++) {
    double a;
    cin >> a;
    orange = orange + a;
  }
  cout << orange / total * 100.000000000000;
}
