#include <bits/stdc++.h>
using namespace std;
void Time() {
  ios::sync_with_stdio(0);
  ios_base::sync_with_stdio(0);
  cin.tie(0), cout.tie(0);
}
bool Prime(long long n) {
  bool res = false;
  int counter = 0;
  for (int i = 2; i < n; i++) {
    if (n % i == 0) {
      counter++;
      break;
    }
  }
  if (counter == 1) {
    res = true;
    return res;
  } else {
    res = false;
    return res;
  }
}
int main() {
  Time();
  double n, m, sum = 0, akmal;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> m;
    sum += m;
  }
  akmal = (sum / (n * 100)) * 100;
  cout << fixed << setprecision(12) << akmal << endl;
  return 0;
}
