#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  float p, total = 0;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> p;
    p = p / 100;
    total = total + p;
  }
  total = 100 * (total / n);
  cout << total;
  return 0;
}
