#include <bits/stdc++.h>
using namespace std;
auto speedup = []() {
  std::ios::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  return nullptr;
}();
const long long int mod = 1e9 + 7;
bool prime(long long int n) {
  if (n < 2) return false;
  for (long long int i = 2; i < sqrt(n) + 1; i++)
    if (n % i == 0) return false;
  return true;
}
void solve() {
  long long int n;
  cin >> n;
  double sum = 0.0;
  for (long long int i = 0; i < n; i++) {
    long long int temp;
    cin >> temp;
    sum += temp;
  }
  cout << fixed << setprecision(12) << double(sum / n);
}
int main() { solve(); }
