#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  double s = 0, x = 0;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> x;
    s = s + x / 100;
  }
  cout << setprecision(12) << s / n * 100;
  return 0;
}
